|Systematic (IUPAC) name|
|Pregnancy cat.||A (AU)|
|Legal status||POM (UK) ℞-only (US)|
|Routes||Intranasal, IV, IM|
|Excretion||Biliary and renal|
|Mol. mass||1007.19 g/mol|
|(what is this?)|
Oxytocin plays an important role in the neuroanatomy of intimacy, specifically in sexual reproduction, in particular during and after childbirth. It is released in large amounts after distension of the cervix and uterus during labor, facilitating birth, maternal bonding, and, after stimulation of the nipples, lactation. Both childbirth and milk ejection result from positive feedback mechanisms.
Recent studies have begun to investigate oxytocin's role in various behaviors, including orgasm, social recognition, pair bonding, anxiety, and maternal behaviors. For this reason, it is sometimes referred to as the "bonding hormone". There is some evidence that oxytocin promotes ethnocentric behavior, incorporating the trust and empathy of in-groups with their suspicion and rejection of outsiders. Furthermore, genetic differences in the oxytocin receptor gene (OXTR) have been associated with maladaptive social traits such as aggressive behaviour.
It is on the World Health Organization's List of Essential Medicines, a list of the most important medication needed in a basic health system.
- 1 Medical uses
- 2 Side effects
- 3 Structure and relation to vasopressin
- 4 Actions
- 5 Synthesis, storage, and release
- 6 Evolution
- 7 Fear and anxiety response
- 8 History
- 9 References
- 10 Further reading
- 11 External links
Injected oxytocin analogues are used for labor induction and to support labor in case of difficult parturition. It has largely replaced ergometrine as the principal agent to increase uterine tone in acute postpartum hemorrhage. Oxytocin is also used in veterinary medicine to facilitate birth and to stimulate milk release. The tocolyticagent atosiban (Tractocile) acts as an antagonist of oxytocin receptors; this drug is registered in many countries to suppress premature labor between 24 and 33 weeks of gestation. It has fewer side effects than drugs previously used for this purpose (ritodrine, salbutamol, and terbutaline).
Synthetic oxytocin is sold as proprietary medication under the trade names Pitocin and Syntocinon, and as generic oxytocin. Oxytocin is destroyed in the gastrointestinal tract, so it must be administered by injection or as nasal spray. It has a half-life of typically about three minutes in the blood, and given intravenously does not enter the brain in significant quantities – it is excluded from the brain by the blood–brain barrier. Evidence in rhesus macaques indicates that administration of oxytocin by nasal spray elevates oxytocin levels in the brain but does not prove that it enters the brain, as opposed to stimulating release from neurons within the brain via olfactory nerve stimulation, for example. Oxytocin nasal sprays have been used to stimulate breastfeeding, but the efficacy of this approach is doubtful.
The trust-inducing property of oxytocin might help those who suffer from social anxieties and mood disorders, but with the potential for abuse with confidence tricks and military applications.
- Subarachnoid hemorrhage
- Increased heart rate
- Decreased blood pressure
- Cardiac arrhythmia and premature ventricular contraction
- Impaired uterine blood flow
- Pelvic hematoma
- Afibrinogenonemia, which can lead to hemorrhage and death
- Nausea and vomiting
Excessive dosage or long-term administration (over a period of 24 hours or longer) have been known to result in tetanic uterine contractions, uterine rupture, postpartum hemorrhage, and water intoxication, sometimes fatal.
Increased uterine motility has led to the following complications in the fetus/neonate:
Structure and relation to vasopressin
Oxytocin is a peptide of nine amino acids (a nonapeptide). Its systematic name is cysteine-tyrosine-isoleucine-glutamine-asparagine-cysteine-proline-leucine-glycine-amide (cys – tyr – ile – gln – asn – cys – pro – leu – gly – NH2, or CYIQNCPLG-NH2). Oxytocin has a molecular mass of 1007 daltons. One international unit (IU) of oxytocin is the equivalent of about 2 micrograms of pure peptide. While the structure of oxytocin is highly conserved in placental mammals, a novel structure of oxytocin was recently reported in marmosets, tamarins, and other new world primates. Genomic sequencing of the gene for oxytocin revealed a single in-frame mutation (thymine for cytosine) which results in a single amino acid substitution at the 8-position (proline for leucine).
The biologically active form of oxytocin, commonly measured by RIA and/or HPLC techniques, is also known as the octapeptide "oxytocin disulfide" (oxidized form), but oxytocin also exists as a reduced dithiol nonapeptide called oxytoceine. It has been theorized that open chain oxytoceine (the reduced form of oxytocin) may also act as a free radical scavenger (by donating an electron to a free radical); oxytoceine may then be oxidized back to oxytocin via the redox potential of dehydroascorbate <---> ascorbate.
The structure of oxytocin is very similar to that of vasopressin (cys – tyr – phe – gln – asn – cys – pro – arg – gly – NH2), also a nonapeptide with a sulfur bridge, whose sequence differs from oxytocin by two amino acids. A table showing the sequences of members of the vasopressin/oxytocin superfamily and the species expressing them is present in the vasopressin article. Oxytocin and vasopressin were isolated and synthesized by Vincent du Vigneaud in 1953, work for which he received the Nobel Prize in Chemistry in 1955.
Oxytocin and vasopressin are the only known hormones released by the human posterior pituitary gland to act at a distance. However, oxytocin neurons make other peptides, including corticotropin-releasing hormone and dynorphin, for example, that act locally. The magnocellular neurosecretory cells that make oxytocin are adjacent to magnocellular neurosecretory cells that make vasopressin. These are large neuroendocrine neurons which are excitable and can generate action potentials.
Oxytocin has peripheral (hormonal) actions, and also has actions in the brain. Its actions are mediated by specific, high-affinity oxytocin receptors. The oxytocin receptor is a G-protein-coupled receptor that requires Mg2+ and cholesterol. It belongs to the rhodopsin-type (class I) group of G-protein-coupled receptors.
Peripheral (hormonal) actions
- Letdown reflex: In lactating (breastfeeding) mothers, oxytocin acts at the mammary glands, causing milk to be 'let down' into subareolar sinuses, from where it can be excreted via the nipple. Suckling by the infant at the nipple is relayed by spinal nerves to the hypothalamus. The stimulation causes neurons that make oxytocin to fire action potentials in intermittent bursts; these bursts result in the secretion of pulses of oxytocin from the neurosecretory nerve terminals of the pituitary gland.
- Uterine contraction: Important for cervical dilation before birth, oxytocin causes contractions during the second and third stages of labor. Oxytocin release during breastfeeding causes mild but often painful contractions during the first few weeks of lactation. This also serves to assist the uterus in clotting the placental attachment point postpartum. However, in knockout mice lacking the oxytocin receptor, reproductive behavior and parturition are normal.
- Social behavior and wound healing: Oxytocin is also thought to modulate inflammation by decreasing certain cytokines. Thus, the increased release in oxytocin following positive social interactions has the potential to improve wound healing. A study by Marazziti and colleagues used heterosexual couples to address this possibility. They found increases in plasma oxytocin following a social interaction were correlated with faster wound healing. They hypothesized this was due to oxytocin reducing inflammation, thus allowing the wound to heal faster. This study provides preliminary evidence that positive social interactions may directly impact aspects of health.
- The relationship between oxytocin and human sexual response is unclear. At least two uncontrolled studies have found increases in plasma oxytocin at orgasm – in both men and women. Plasma oxytocin levels are notably increased around the time of self-stimulated orgasm and are still higher than baseline when measured five minutes after self arousal. The authors of one of these studies speculated that oxytocin's effects on muscle contractibility may facilitate sperm and egg transport.
- In a study measuring oxytocin serum levels in women before and after sexual stimulation, the author suggests it serves an important role in sexual arousal. This study found genital tract stimulation resulted in increased oxytocin immediately after orgasm. Another study reported increases of oxytocin during sexual arousal could be in response to nipple/areola, genital, and/or genital tract stimulation as confirmed in other mammals. Murphy et al. (1987), studying men, found oxytocin levels were raised throughout sexual arousal with no acute increase at orgasm. A more recent study of men found an increase in plasma oxytocin immediately after orgasm, but only in a portion of their sample that did not reach statistical significance. The authors noted these changes "may simply reflect contractile properties on reproductive tissue".
- Oxytocin evokes feelings of contentment, reductions in anxiety, and feelings of calmness and security around the mate. This suggests oxytocin may be important for the inhibition of the brain regions associated with behavioral control, fear, and anxiety, thus allowing orgasm to occur. Oxytocin also functions to protect against stress. Meta-analyses conducted in 2003 demonstrated that oxytocin can alleviate mood and reduce stress with a good efficiency.
- Due to its similarity to vasopressin, it can reduce the excretion of urine slightly. In several species, oxytocin can stimulate sodium excretion from the kidneys (natriuresis), and, in humans, high doses can result in hyponatremia.
- Oxytocin and oxytocin receptors are also found in the heart in some rodents, and the hormone may play a role in the embryonal development of the heart by promoting cardiomyocyte differentiation. However, the absence of either oxytocin or its receptor in knockout mice has not been reported to produce cardiac insufficiencies.
- Modulation of hypothalamic-pituitary-adrenal axis activity: Oxytocin, under certain circumstances, indirectly inhibits release of adrenocorticotropic hormone and cortisol and, in those situations, may be considered an antagonist of vasopressin.
- Autism: Oxytocin may play a role in autism and may be an effective treatment for autism's repetitive and affiliative behaviors. Oxytocin treatments also resulted in an increased retention of affective speech in adults with autism. Two related studies in adults, in 2003 and 2007, found oxytocin decreased repetitive behaviors and improved interpretation of emotions. More recently, intranasal administration of oxytocin was found to increase emotion recognition in children as young as 12 who are diagnosed with autism spectrum disorders. Oxytocin has also been implicated in the etiology of autism, with one report suggesting autism is correlated with genomic deletion of the gene containing the oxytocin receptor gene (OXTR). Studies involving Caucasian and Finnish samples and Chinese Han families provide support for the relationship of OXTR with autism. Autism may also be associated with an aberrant methylation of OXTR. After treatment with inhaled oxytocin, autistic patients exhibit more appropriate social behavior. While this research suggests some promise, further clinical trials of oxytocin are required to demonstrate potential benefit and side effects in the treatment of autism. As such, researchers do not recommend use of oxytocin as a treatment for autism outside of clinical trials.
- Increasing trust and reducing fear: In a risky investment game, experimental subjects given nasally administered oxytocin displayed "the highest level of trust" twice as often as the control group. Subjects who were told they were interacting with a computer showed no such reaction, leading to the conclusion that oxytocin was not merely affecting risk aversion. Nasally administered oxytocin has also been reported to reduce fear, possibly by inhibiting the amygdala (which is thought to be responsible for fear responses). Indeed, studies in rodents have shown oxytocin can efficiently inhibit fear responses by activating an inhibitory circuit within the amygdala. Some researchers have argued oxytocin has a general enhancing effect on all social emotions, since intranasal administration of oxytocin also increases envy and Schadenfreude.
- Trust is increased by oxytocin. Disclosure of emotional events is a sign of trust in humans. When recanting a negative event, humans that receive intranasal oxytocin share more emotional details and stories with more emotional significance. Humans also find faces more trustworthy after receiving intranasal oxytocin. In a study, participants that received intranasal oxytocin viewed photographs of human faces with neutral expressions and found them to be more trustworthy than those who did not receive oxytocin. This may be because oxytocin reduces the fear of social betrayal in humans. Even after experiencing social alienation by being excluded from a conversation, humans that received oxytocin scored higher in trust on the Revised NEO Personality Inventory.
- While Oxytocin increases trust, it does so only to a certain degree. In a study, participants played a variation of the trust game and acted as an “investor,” deciding how much money to allocate to a “trustee.” The trustee was described as trustworthy, untrustworthy, or neutral. Participants that received intranasal oxytocin gave more money to the trustworthy and neutral trustees. Participants that received oxytocin did not give more money to the untrustworthy trustee, implying that oxytocin only increases trust when there is no reason to be distrustful. When there is a reason to be distrustful, such as experiencing betrayal, differing reactions are associated with oxytocin receptor gene (OXTR) differences. Those with the CT haplotype experience a stronger reaction, in the form of anger, to betrayal.
- Oxytocin affects social distance between adult males and females, and may be responsible at least in part for romantic attraction and subsequent monogamous pair bonding. An oxytocin nasal spray caused men in a monogamous relationship, but not single men, to increase the distance between themselves and an attractive woman during a first encounter by 10 to 15 centimeters. The researchers suggested that oxytocin may help promote fidelity within monogamous relationships.
- Affecting generosity by increasing empathy during perspective taking: In a neuroeconomics experiment, intranasal oxytocin increased generosity in the Ultimatum Game by 80%, but had no effect in the Dictator Game that measures altruism. Perspective-taking is not required in the Dictator Game, but the researchers in this experiment explicitly induced perspective-taking in the Ultimatum Game by not identifying to participants into which role they would be placed. Serious methodological questions have arisen, however, with regard to the role of oxytocin in trust and generosity.
- Empathy in healthy males has been shown to be increased after intranasal oxytocin This is most likely due to the effect of oxytocin in enhancing eye gaze. There is some discussion about which aspect of empathy oxytocin might alter – for example, cognitive vs. emotional empathy.
- Cognitive function: Certain learning and memory functions are impaired by centrally administered oxytocin. Also, systemic oxytocin administration can impair memory retrieval in certain aversive memory tasks. Interestingly, oxytocin does seem to facilitate learning and memory specifically for social information. Healthy males administered intranasal oxytocin show improved memory for human faces, in particular happy faces. They also show improved recognition for positive social cues over threatening social cues  and improved recognition of fear.
Actions within the brain
Oxytocin secreted from the pituitary gland cannot re-enter the brain because of the blood–brain barrier. Instead, the behavioral effects of oxytocin are thought to reflect release from centrally projecting oxytocin neurons, different from those that project to the pituitary gland, or that are collaterals from them. Oxytocin receptors are expressed by neurons in many parts of the brain and spinal cord, including the amygdala, ventromedial hypothalamus, septum, nucleus accumbens, and brainstem.
- Sexual arousal: Oxytocin injected into the cerebrospinal fluid causes spontaneous erections in rats, reflecting actions in the hypothalamus and spinal cord. Centrally administrated oxytocin receptor antagonists can prevent noncontact erections, which is a measure of sexual arousal. Studies using oxytocin antagonists in female rats provide data that oxytocin increases lordosis behavior, indicating an increase in sexual receptivity.
- Bonding: In the prairie vole, oxytocin released into the brain of the female during sexual activity is important for forming a monogamous pair bond with her sexual partner. Vasopressin appears to have a similar effect in males. Oxytocin has a role in social behaviors in many species, so it likely also does in humans. In a 2003 study, both humans and dog oxytocin levels in the blood rose after five to 24 minutes of a petting session. This possibly plays a role in the emotional bonding between humans and dogs.
- Maternal behavior: Female rats given oxytocin antagonists after giving birth do not exhibit typical maternal behavior. By contrast, virgin female sheep show maternal behavior toward foreign lambs upon cerebrospinal fluid infusion of oxytocin, which they would not do otherwise. Oxytocin is involved in the initiation of maternal behavior, not its maintenance; for example, it is higher in mothers after they interact with unfamiliar children rather than their own.
- Drug interactions: According to some studies in animals, oxytocin inhibits the development of tolerance to various addictive drugs (opiates, cocaine, alcohol), and reduces withdrawal symptoms. MDMA (ecstasy) may increase feelings of love, empathy, and connection to others by stimulating oxytocin activity via activation of serotonin 5-HT1A receptors, if initial studies in animals apply to humans. The anxiolytic Buspar (buspirone) also appears to produce some or all of its effect via 5-HT1A receptor-induced oxytocin stimulation.
- Preparing fetal neurons for delivery: Crossing the placenta, maternal oxytocin reaches the fetal brain and induces a switch in the action of neurotransmitter GABA from excitatory to inhibitory on fetal cortical neurons. This silences the fetal brain for the period of delivery and reduces its vulnerability to hypoxic damage.
- Romantic attachment: In some studies, high levels of plasma oxytocin have been correlated with romantic attachment. For example, if a couple is separated for a long period of time, anxiety can increase due to the lack of physical affection. Oxytocin may aid romantically attached couples by decreasing their feelings of anxiety when they are separated.
Synthesis, storage, and release
|Oxytocin/neurophysin I prepropeptide|
|Symbols||; OT; OT-NPI; OXT-NPI|
The oxytocin peptide is synthesized as an inactive precursor protein from the OXT gene. This precursor protein also includes the oxytocin carrier protein neurophysin I. The inactive precursor protein is progressively hydrolyzed into smaller fragments (one of which is neurophysin I) via a series of enzymes. The last hydrolysis that releases the active oxytocin nonapeptide is catalyzed by peptidylglycine alpha-amidating monooxygenase (PAM).
The activity of the PAM enzyme system is dependent upon vitamin C (ascorbate), which is a necessary vitamin cofactor. By chance, sodium ascorbate by itself was found to stimulate the production of oxytocin from ovarian tissue over a range of concentrations in a dose-dependent manner. Many of the same tissues (e.g. ovaries, testes, eyes, adrenals, placenta, thymus, pancreas) where PAM (and oxytocin by default) is found are also known to store higher concentrations of vitamin C.
In the hypothalamus, oxytocin is made in magnocellular neurosecretory cells of the supraoptic and paraventricular nuclei, and is stored in Herring bodies at the axon terminals in the posterior pituitary. It is then released into the blood from the posterior lobe (neurohypophysis) of the pituitary gland. These axons (likely, but dendrites have not been ruled out) have collaterals that innervate oxytocin receptors in the nucleus accumbens. The peripheral hormonal and behavioral brain effects of oxytocin are thought to be coordinated through its common release through these collaterals. Oxytocin is also made by some neurons in the paraventricular nucleus that project to other parts of the brain and to the spinal cord. Depending on the species, oxytocin receptor-expressing cells are located in other areas, including the amygdala and bed nucleus of the stria terminalis.
In the pituitary gland, oxytocin is packaged in large, dense-core vesicles, where it is bound to neurophysin I as shown in the inset of the figure; neurophysin is a large peptide fragment of the larger precursor protein molecule from which oxytocin is derived by enzymatic cleavage.
Secretion of oxytocin from the neurosecretory nerve endings is regulated by the electrical activity of the oxytocin cells in the hypothalamus. These cells generate action potentials that propagate down axons to the nerve endings in the pituitary; the endings contain large numbers of oxytocin-containing vesicles, which are released by exocytosis when the nerve terminals are depolarised.
Outside the brain, oxytocin-containing cells have been identified in several diverse tissues, including the corpus luteum, the interstitial cells of Leydig, the retina, the adrenal medulla, the placenta, the thymus and the pancreas. The finding of significant amounts of this classically "neurohypophysial" hormone outside the central nervous system raises many questions regarding its possible importance in these different tissues.
Oxytocin is synthesized by corpora lutea of several species, including ruminants and primates. Along with estrogen, it is involved in inducing the endometrial synthesis of prostaglandin F2α to cause regression of the corpus luteum.
The Leydig cells in some species have also been shown to possess the biosynthetic machinery to manufacture testicular oxytocin de novo, to be specific, in rats (which can synthesize vitamin C endogenously), and in guinea pigs, which, like humans, require an exogenous source of vitamin C (ascorbate) in their diets.
Virtually all vertebrates have an oxytocin-like nonapeptide hormone that supports reproductive functions and a vasopressin-like nonapeptide hormone involved in water regulation. The two genes are usually located close to each other (less than 15,000 bases apart) on the same chromosome, and are transcribed in opposite directions (however, in fugu, the homologs are further apart and transcribed in the same direction).
Fear and anxiety response
Oxytocin is typically remembered for the effect it has on prosocial behaviors, such as its role in facilitating trust and attachment between individuals. Consequently, oxytocin is often referred to as the “love hormone". However, oxytocin has a larger, and more complex role than solely enhancing prosocial behaviors. Oxytocin also plays a role in enhancing fear and anxiety.
There is a consensus that oxytocin has a modulatory effect on fear and anxiety; that is, oxytocin does not directly elicit fear or anxiety. There are two dominant theories explaining the role oxytocin plays in fear and anxiety. One theory states that oxytocin increases approach/avoidance to certain social stimuli. The second theory states that oxytocin increases the salience of certain social stimuli, causing the animal or human to pay closer attention to socially relevant stimuli.
Individuals who receive an intranasal dose of oxytocin identify facial expressions of disgust faster than individuals who do not receive oxytocin. Facial expressions of disgust are evolutionarily linked to the idea of contagion. Thus, oxytocin increases the salience of cues that imply contamination, which leads to a faster response because these cues are especially relevant for survival. In another study, after administration of oxytocin, individuals displayed an enhanced ability to recognize expressions of fear compared to the individuals who received the placebo. Oxytocin modulates fear responses by enhancing the maintenance of social memories. Rats that are genetically modified to have a surplus of oxytocin receptors display a greater fear response to a previously conditioned stressor. Oxytocin enhances the aversive social memory, leading the rat to display a greater fear response when the aversive stimulus is encountered again.
- Gender differences
To make the role of oxytocin even more complex, it has been shown that oxytocin differentially affects males and females. Females who are administered oxytocin are overall faster in responding to socially relevant stimuli than males who received oxytocin. Additionally, after the administration of oxytocin, females show increased amygdala activity in response to threatening scenes; however, males do not show increased amygdala activation. This phenomenon can be explained by looking at the role of gonadal hormones, specifically estrogen, which modulate the enhanced threat processing seen in females. Estrogen has been shown to stimulate the release of oxytocin from the hypothalamus and promote receptor binding in the amygdala.
- Effect in predictable and unpredictable stimuli
Oxytocin increases defensive responding to unpredictable stimuli, but not to predictable stimuli. This result leads to the assumption that oxytocin’s effect is context-dependent. Thus, oxytocin may reinforce prosocial behaviors after an initial bond is formed, but may enhance defensive behaviors to unfamiliar individuals.
Oxytocin is beneficial because it can either enhance social bonding or promote defensive behaviors depending on the situation. It would not be adaptive if oxytocin consistently enhanced social approach and other prosocial behaviors, especially in uncertain and potentially dangerous social contexts. Fear and anxiety are typically thought to be maladaptive, as these traits often underlie various psychological disorders. However, it is important to note that both fear and anxiety responses help to protect an individual. These emotions render environmental cues more important, leading to a greater likelihood the individual or animal will acknowledge the potential threat. Ultimately this process leads to a greater chance of survival.
The word oxytocin was coined from the term oxytocic (used at least in the 1800s to refer to agents such as ergots that would cause uterine stimulation; Greekὀξύς, oxys, and τόκος, tokos, meaning "quick birth") by chemists at Parke, Davis, and Company around 1927, two decades after its uterine-contracting properties were discovered by British pharmacologist SirHenry Hallett Dale in 1906. The milk ejection property of oxytocin was described by Ott and Scott in 1910 and by Schafer and Mackenzie in 1911.
The nine amino acid sequence of oxytocin was elucidated by Vincent du Vigneaud et al.and by Tuppy in 1953 and synthesized biochemically soon after by du Vigneaud et al. in 1953. Oxytocin was the first polypeptide hormone to be sequenced and synthesized. Vigneaud was awarded the Nobel Prize in 1955 for his work.
- Marieb Human Anatomy & Physiology 9th edition, chapter:16, page:599
- Lee HJ, Macbeth AH, Pagani JH, Young WS (June 2009). "Oxytocin: the great facilitator of life". Prog. Neurobiol. 88 (2): 127–51. doi:10.1016/j.pneurobio.2009.04.001. PMC 2689929. PMID 19482229.
- De Dreu CK, Greer LL, Van Kleef GA, Shalvi S, Handgraaf MJ (January 2011). "Oxytocin promotes human ethnocentrism". Proc. Natl. Acad. Sci. U.S.A. 108 (4): 1262–6. doi:10.1073/pnas.1015316108. PMC 3029708. PMID 21220339.
- Malik AI, Zai CC, Abu Z, Nowrouzi B, Beitchman JH (July 2012). "The role of oxytocin and oxytocin receptor gene variants in childhood-onset aggression". Genes Brain Behav. 11 (5): 545–51. doi:10.1111/j.1601-183X.2012.00776.x. PMID 22372486.
- "WHO Model List of EssentialMedicines". World Health Organization. October 2013. Retrieved 22 April 2014.
- Chang SWC, Barter JW, Ebitz RB, Watson KK, Platt ML (2012). "Inhaled oxytocin amplifies both vicarious reinforcement and self reinforcement in rhesus macaques (Macaca mulatta)". Proc Natl Acad Sci U S A. 109 (3): 959–64. doi:10.1073/pnas.1114621109. PMC 3271866. PMID 22215593.
- Fewtrell MS, Loh KL, Blake A, Ridout DA, Hawdon J (May 2006). "Randomised, double blind trial of oxytocin nasal spray in mothers expressing breast milk for preterm infants". Archives of Disease in Childhood. Fetal and Neonatal Edition 91 (3): F169–74. doi:10.1136/adc.2005.081265. PMC 2672698. PMID 16223754.
- Hurlemann R, Patin A, Onur OA, Cohen MX, Baumgartner T, Metzler S, Dziobek I, Gallinat J, Wagner M, Maier W, Kendrick KM (April 2010). "Oxytocin enhances amygdala-dependent, socially reinforced learning and emotional empathy in humans". J. Neurosci. 30 (14): 4999–5007. doi:10.1523/JNEUROSCI.5538-09.2010. PMID 20371820.
- Petrovic P, Kalisch R, Singer T, Dolan RJ (June 2008). "Oxytocin Attenuates Affective Evaluations of Conditioned Faces and Amygdala Activity". The Journal of Neuroscience 28 (26): 6607–15. doi:10.1523/JNEUROSCI.4572-07.2008. PMC 2647078. PMID 18579733.
- "To sniff at danger – Mind Matters". Health And Fitness (Boston Globe). 2006-01-12. Retrieved 2009-04-13.
- Dando M (August 2009). "Biologists napping while work militarized". Nature 460 (7258): 950–1. doi:10.1038/460950a. PMID 19693065. Lay summary – Reuters.
- "Pitocin (drug label for professionals)". Rx List. WebMD. Retrieved 2010-09-09.
- Lee AG, Cool DR, Grunwald WC, Neal DE, Buckmaster CL, Cheng MY, Hyde SA, Lyons DM, Parker KJ (August 2011). "A novel form of oxytocin in New World monkeys". Biol. Lett. 7 (4): 584–7. doi:10.1098/rsbl.2011.0107. PMC 3130245. PMID 21411453.
- du Vigneaud V. (1960). "Experiences in the Polypeptide Field: Insulin to Oxytocin". Annals of the New York Academy of Sciences 88 (3): 537–48. doi:10.1111/j.1749-6632.1960.tb20052.x.
- Kukucka MA (1993-04-18). "Mechanisms by which hypoxia augments Leydig cell viability and differentiated cell function in vitro". Digital Library and Archives. Retrieved 2010-02-21.
- Takayanagi Y, Yoshida M, Bielsky IF, Ross HE, Kawamata M, Onaka T, Yanagisawa T, Kimura T, Matzuk MM, Young LJ, Nishimori K (November 2005). "Pervasive social deficits, but normal parturition, in oxytocin receptor-deficient mice". Proc. Natl. Acad. Sci. U.S.A. 102 (44): 16096–101. doi:10.1073/pnas.0505312102. PMC 1276060. PMID 16249339.
- Zak PJ, Kurzban R, Matzner WT (December 2004). "The neurobiology of trust". Ann. N. Y. Acad. Sci. 1032: 224–7. doi:10.1196/annals.1314.025. PMID 15677415.
- Gouin JP, Carter S, Pournajafi-Nazarloo H, Glaser R, Malarkey WB, Loving TJ, Stowell J, and Kiecolt-Glaser JK (2010). "Marital Behavior, Oxytocin, Vasopressin, and Wound Healing". Psychoneuroendocrinology 35 (7): 1082–1090. doi:10.1016/j.psyneuen.2010.01.009. PMC 2888874. PMID 20144509.
- Carmichael MS, Humbert R, Dixen J, Palmisano G, Greenleaf W, Davidson JM (January 1987). "Plasma oxytocin increases in the human sexual response". The Journal of Clinical Endocrinology and Metabolism 64 (1): 27–31. doi:10.1210/jcem-64-1-27. PMID 3782434.
- Carmichael MS, Warburton VL, Dixen J, Davidson JM (February 1994). "Relationships among cardiovascular, muscular, and oxytocin responses during human sexual activity". Archives of Sexual Behavior 23 (1): 59–79. doi:10.1007/BF01541618. PMID 8135652.
- Blaicher W, Gruber D, Bieglmayer C, Blaicher AM, Knogler W, Huber JC (1999). "The role of oxytocin in relation to female sexual arousal". Gynecologic and Obstetric Investigation 47 (2): 125–6. doi:10.1159/000010075. PMID 9949283.
- Anderson-Hunt M, Dennerstein L (1995). "Oxytocin and female sexuality". Gynecologic and Obstetric Investigation 40 (4): 217–21. doi:10.1159/000292340. PMID 8586300.
- Murphy MR, Seckl JR, Burton S, Checkley SA, Lightman SL (October 1987). "Changes in oxytocin and vasopressin secretion during sexual activity in men". The Journal of Clinical Endocrinology and Metabolism 65 (4): 738–41. doi:10.1210/jcem-65-4-738. PMID 3654918.
- Krüger TH, Haake P, Chereath D, Knapp W, Janssen OE, Exton MS, Schedlowski M, Hartmann U (April 2003). "Specificity of the neuroendocrine response to orgasm during sexual arousal in men". J. Endocrinol. 177 (1): 57–64. doi:10.1677/joe.0.1770057. PMID 12697037.
- Marazziti D, Dell'Osso B, Baroni S, Mungai F, Catena M, Rucci P, Albanese F, Giannaccini G, Betti L, Fabbrini L, Italiani P, Del Debbio A, Lucacchini A, Dell'Osso L (2006). "A relationship between oxytocin and anxiety of romantic attachment". Clin Pract Epidemiol Ment Health 2: 28. doi:10.1186/1745-0179-2-28. PMC 1621060. PMID 17034623.
- Poquérusse J. "The Neuroscience of Sharing". Retrieved 16 August 2012.
- Paquin J, Danalache BA, Jankowski M, McCann SM, Gutkowska J (July 2002). "Oxytocin induces differentiation of P19 embryonic stem cells to cardiomyocytes". Proceedings of the National Academy of Sciences of the United States of America 99 (14): 9550–5. doi:10.1073/pnas.152302499. PMC 123178. PMID 12093924.
- Jankowski M, Danalache B, Wang D, Bhat P, Hajjar F, Marcinkiewicz M, Paquin J, McCann SM, Gutkowska J (August 2004). "Oxytocin in cardiac ontogeny". Proc. Natl. Acad. Sci. U.S.A. 101 (35): 13074–9. doi:10.1073/pnas.0405324101. PMC 516519. PMID 15316117.
- Hartwig, Walenty (1989). Endokrynologia praktyczna. Warsaw: Państwowy Zakład Wydawnictw Lekarskich. ISBN 83-200-1415-8.[page needed]
- Bartz JA, Hollander E (2008). "Oxytocin and experimental therapeutics in autism spectrum disorders". Progress in Brain Research. Progress in Brain Research 170: 451–62. doi:10.1016/S0079-6123(08)00435-4. ISBN 978-0-444-53201-5. PMID 18655901.
- Jacob S, Brune CW, Carter CS, Leventhal BL, Lord C, Cook EH (April 2007). "Association of the Oxytocin Receptor Gene (OXTR) in Caucasian Children and Adolescents with Autism". Neuroscience Letters 417 (1): 6–9. doi:10.1016/j.neulet.2007.02.001. PMC 2705963. PMID 17383819.
- Guastella AJ, Einfeld EL, Gray, K, Rinehart N, Tonge B, Lambert TJ, Hickie IB (April 2010). "Intranasal oxytocin improves emotion recognition for youth with autism spectrum disorders". Biological Psychiatry 67 (7): 692–4. doi:10.1016/j.biopsych.2009.09.020. PMID 19897177.
- Wermter AK, Kamp-Becker I, Hesse P, Schulte-Körne G, Strauch K, Remschmidt H (September 2009). "Evidence for the involvement of genetic variation in the oxytocin receptor gene (OXTR) in the etiology of autistic disorders on high-functioning level". American Journal of Medical Genetics 153B (2): 629–39. doi:10.1002/ajmg.b.31032. PMID 19777562.
- Andaria E, Duhamela J-R, Zallab T, Herbrechtb E, Leboyerb M, Sirigu A (2010). "Promoting social behavior with oxytocin in high-functioning autism spectrum disorders". Proc. Natl. Acad. Sci. U.S.A. 107 (9): 4389–94. doi:10.1073/pnas.0910249107. PMC 2840168. PMID 20160081. Lay summary – Scientific American.
- Gordon I, Vander Wyk BC, Bennett RH, Cordeaux C, Lucas MV, Eilbott JA, Zagoory-Sharon O, Leckman JF, Feldman R, Pelphrey KA (2013). "Oxytocin enhances brain function in children with autism". Proc. Natl. Acad. Sci. U.S.A. doi:10.1073/pnas.1312857110. Lay summary – New York Times.
- Kosfeld M, Heinrichs M, Zak PJ, Fischbacher U, Fehr E (June 2005). "Oxytocin increases trust in humans". Nature 435 (7042): 673–6. doi:10.1038/nature03701. PMID 15931222.
- Kirsch P, Esslinger C, Chen Q, Mier D, Lis S, Siddhanti S, Gruppe H, Mattay VS, Gallhofer B, Meyer-Lindenberg A (December 2005). "Oxytocin modulates neural circuitry for social cognition and fear in humans". J. Neurosci. 25 (49): 11489–93. doi:10.1523/JNEUROSCI.3984-05.2005. PMID 16339042.
- Huber D, Veinante P and Stoop R (April 2005). "Vasopressin and oxytocin excite distinct neuronal populations in the central amygdala". Science 308 (5719): 245–8. doi:10.1126/SCIENCE.1105636. PMID 15821089.
- Viviani D, Charlet A, van den Burg E, Robinet C, Hurni N, Abatis M, Magara F, Stoop R. (July 2011). "Oxytocin selectively gates fear responses through distinct outputs from the central amygdala". Science 333 (6038): 104–7. doi:10.1126/SCIENCE.1201043. PMID 21719680.
- Shamay-Tsoory SG, Fischer M, Dvash J, Harari H, Perach-Bloom N, Levkovitz Y (November 2009). "Intranasal administration of oxytocin increases envy and schadenfreude (gloating)". Biological Psychiatry 66 (9): 864–70. doi:10.1016/j.biopsych.2009.06.009. PMID 19640508.
- Theodoridou A, Rowe AC, Penton-Voak IS, Rogers PJ (June 2009). "Oxytocin and social perception: oxytocin increases perceived facial trustworthiness and attractiveness". Horm Behav 56 (1): 128–32. doi:10.1016/j.yhbeh.2009.03.019. PMID 19344725.
- Lane A, Luminet O, Rimé B, Gross JJ, de Timary P, Mikolajczak M (2013). "Oxytocin increases willingness to socially share one's emotions". Int J Psychol 48 (4): 676–81. doi:10.1080/00207594.2012.677540. PMID 22554106.
- Cardoso C, Ellenbogen MA, Serravalle L, Linnen AM (November 2013). "Stress-induced negative mood moderates the relation between oxytocin administration and trust: evidence for the tend-and-befriend response to stress?". Psychoneuroendocrinology 38 (11): 2800–4. doi:10.1016/j.psyneuen.2013.05.006. PMID 23768973.
- Baumgartner T, Heinrichs M, Vonlanthen A, Fischbacher U, Fehr E (May 2008). "Oxytocin shapes the neural circuitry of trust and trust adaptation in humans". Neuron 58 (4): 639–50. doi:10.1016/j.neuron.2008.04.009. PMID 18498743.
- Mikolajczak M, Gross JJ, Lane A, Corneille O, de Timary P, Luminet O (August 2010). "Oxytocin makes people trusting, not gullible". Psychol Sci 21 (8): 1072–4. doi:10.1177/0956797610377343. PMID 20631321.
- Tabak BA, McCullough ME, Carver CS, Pedersen EJ, Cuccaro ML (May 2013). "Variation in oxytocin receptor gene (OXTR) polymorphisms is associated with emotional and behavioral reactions to betrayal". Soc Cogn Affect Neurosci. doi:10.1093/scan/nst042. PMID 23547247.
- Scheele D, Striepens N, Güntürkün O, Deutschländer S, Maier W, Kendrick KM, Hurlemann R (November 2012). "Oxytocin modulates social distance between males and females". J. Neurosci. 32 (46): 16074–9. doi:10.1523/JNEUROSCI.2755-12.2012. PMID 23152592.
- Zak PJ, Stanton AA, Ahmadi S (2007). "Oxytocin Increases Generosity in Humans". In Brosnan, Sarah. PLoS ONE 2 (11): e1128. doi:10.1371/journal.pone.0001128. PMC 2040517. PMID 17987115.
- Conlisk J (2011). "Professor Zak's empirical studies on trust and oxytocin". J Econ Behav Organizat 78 (1–2): 160–166. doi:10.1016/j.jebo.2011.01.002.
- Domes G, Heinrichs M, Michel A, Berger C, Herpertz SC (April 2010). "Oxytocin improves "mind-reading" in humans". Biological Psychiatry 61 (6): 731–3. doi:10.1016/j.biopsych.2006.07.015. PMID 17137561.
- Guastella AJ, Mitchell PB, Dadds MR (Jan 2008). "Oxytocin increases gaze to the eye region of human faces". Biological Psychiatry 63 (1): 3–5. doi:10.1016/j.biopsych.2007.06.026. PMID 17888410.
- Singer T, Snozzi R, Bird G, Petrovic P, Silani G, Heinrichs M, Dolan RJ (December 2008). "Effects of Oxytocin and Prosocial Behavior on Brain Responses to Direct and Vicariously Experienced Pain". Emotion 8 (6): 781–91. doi:10.1037/a0014195. PMC 2672051. PMID 19102589.
- Gimpl G, Fahrenholz F (April 2001). "The oxytocin receptor system: structure, function, and regulation". Physiological Reviews 81 (2): 629–83. PMID 11274341.
- de Oliveira LF, Camboim C, Diehl F, Consiglio AR, Quillfeldt JA (January 2007). "Glucocorticoid-mediated effects of systemic oxytocin upon memory retrieval". Neurobiology of Learning and Memory 87 (1): 67–71. doi:10.1016/j.nlm.2006.05.006. PMID 16997585.
- Guastella AJ, Mitchell PB, Matthews F (August 2008). "Oxytocin enhances the encoding of positive social memories in humans". Biological Psychiatry 64 (3): 256–8. doi:10.1016/j.biopsych.2008.02.008. PMID 18343353.
- Rimmele U, Hediger K, Heinrichs M, Klaver P (2009). "Oxytocin makes a face in memory familiar". Journal of Neuroscience 29 (1): 38–42. doi:10.1523/JNEUROSCI.4260-08.2009. PMID 19129382.
- Unkelbach C, Guastella AJ, Forgas JP (Nov 2008). "Oxytocin selectively facilitates recognition of positive sex and relationship words". Psychological Science 19 (11): 1092–4. doi:10.1111/j.1467-9280.2008.02206.x. PMID 19076479.
- Marsh AA, Yu HH, Pine DS, Blair RJ (April 2010). "Oxytocin improves specific recognition of positive facial expressions". Psychopharmacology 209 (3): 225–32. doi:10.1007/s00213-010-1780-4. PMID 20186397.
- Fischer-Shofty M, Shamay-Tsoory SG, Harari H, Levkovitz Y. (January 2010). "The effect of intranasal administration of oxytocin on fear recognition". Neuropsychologia 48 (1): 179–84. doi:10.1016/j.neuropsychologia.2009.09.003. PMID 19747930.
- Ross HE, Cole CD, Smith Y, Neumann ID, Landgraf R, Murphy AZ, Young LJ (September 2009). "Characterization of the oxytocin system regulating affiliative behavior in female prairie voles". Neuroscience 162 (4): 892–903. doi:10.1016/j.neuroscience.2009.05.055. PMC 2744157. PMID 19482070.
- Bancroft J (September 2005). "The endocrinology of sexual arousal". The Journal of Endocrinology 186 (3): 411–27. doi:10.1677/joe.1.06233. PMID 16135662.
- Vacek M, High on Fidelity. What can voles teach us about monogamy?
- Kuchinskas Susan, The Chemistry of Connection: How the Oxytocin Response Can Help You Find Trust, Intimacy, and Love p65
- van Leengoed E, Kerker E, Swanson HH (February 1987). "Inhibition of post-partum maternal behaviour in the rat by injecting an oxytocin antagonist into the cerebral ventricles". J. Endocrinol. 112 (2): 275–82. doi:10.1677/joe.0.1120275. PMID 3819639.
- Kendrick KM (2004-01-01). "The Neurobiology of Social Bonds". British Society for Neuroendocrinology. Retrieved 2009-04-13.
- Bick J, Dozier M (January 2010). "Mothers' and Children's Concentrations of Oxytocin Following Close, Physical Interactions with Biological and Non-biological Children". Dev Psychobiol 52 (1): 100–107. doi:10.1002/dev.20411. PMC 2953948. PMID 20953313.
- Kovács GL, Sarnyai Z, Szabó G (November 1998). "Oxytocin and addiction: a review". Psychoneuroendocrinology 23 (8): 945–62. doi:10.1016/S0306-4530(98)00064-X. PMID 9924746.
- Thompson MR, Callaghan PD, Hunt GE, Cornish JL, McGregor IS (May 2007). "A role for oxytocin and 5-HT(1A) receptors in the prosocial effects of 3,4 methylenedioxymethamphetamine ("ecstasy")". Neuroscience 146 (2): 509–14. doi:10.1016/j.neuroscience.2007.02.032. PMID 17383105.
- Uvnäs-Moberg K, Hillegaart V, Alster P, Ahlenius S (1996). "Effects of 5-HT agonists, selective for different receptor subtypes, on oxytocin, CCK, gastrin and somatostatin plasma levels in the rat". Neuropharmacology 35 (11): 1635–40. doi:10.1016/S0028-3908(96)00078-0. PMID 9025112.
- Chiodera P, Volpi R, Capretti L, Caffarri G, Magotti MG, Coiro V (April 1996). "Different effects of the serotonergic agonists buspirone and sumatriptan on the posterior pituitary hormonal responses to hypoglycemia in humans". Neuropeptides 30 (2): 187–92. doi:10.1016/S0143-4179(96)90086-4. PMID 8771561.
- Tyzio R, Cossart R, Khalilov I, Minlebaev M, Hübner CA, Represa A, Ben-Ari Y, Khazipov R (December 2006). "Maternal oxytocin triggers a transient inhibitory switch in GABA signaling in the fetal brain during delivery". Science 314 (5806): 1788–92. doi:10.1126/science.1133212. PMID 17170309.
- Sausville E, Carney D, Battey J (August 1985). "The human vasopressin gene is linked to the oxytocin gene and is selectively expressed in a cultured lung cancer cell line". J. Biol. Chem. 260 (18): 10236–41. PMID 2991279.
- Repaske DR, Phillips JA, Kirby LT, Tze WJ, D'Ercole AJ, Battey J (March 1990). "Molecular analysis of autosomal dominant neurohypophyseal diabetes insipidus". J. Clin. Endocrinol. Metab. 70 (3): 752–7. doi:10.1210/jcem-70-3-752. PMID 1968469.
- Summar ML, Phillips JA, Battey J, Castiglione CM, Kidd KK, Maness KJ, Weiffenbach B, Gravius TC (June 1990). "Linkage relationships of human arginine vasopressin-neurophysin-II and oxytocin-neurophysin-I to prodynorphin and other loci on chromosome 20". Mol. Endocrinol. 4 (6): 947–50. doi:10.1210/mend-4-6-947. PMID 1978246.
- Brownstein MJ, Russell JT, Gainer H (January 1980). "Synthesis, transport, and release of posterior pituitary hormones". Science 207 (4429): 373–8. doi:10.1126/science.6153132. PMID 6153132.
- Sheldrick EL, Flint AP (July 1989). "Post-translational processing of oxytocin-neurophysin prohormone in the ovine corpus luteum: activity of peptidyl glycine alpha-amidating mono-oxygenase and concentrations of its cofactor, ascorbic acid". J. Endocrinol. 122 (1): 313–22. doi:10.1677/joe.0.1220313. PMID 2769155.
- Luck MR, Jungclas B (September 1987). "Catecholamines and ascorbic acid as stimulators of bovine ovarian oxytocin secretion". J. Endocrinol. 114 (3): 423–30. doi:10.1677/joe.0.1140423. PMID 3668432.
- Hornig D (September 1975). "Distribution of ascorbic acid, metabolites and analogues in man and animals". Annals of the New York Academy of Sciences 258: 103–18. doi:10.1111/j.1749-6632.1975.tb29271.x. PMID 1106295.
- Landgraf R, Neumann ID (2004). "Vasopressin and oxytocin release within the brain: a dynamic concept of multiple and variable modes of neuropeptide communication". Frontiers in Neuroendocrinology 25 (3–4): 150–76. doi:10.1016/j.yfrne.2004.05.001. PMID 15589267.
- Wathes DC, Swann RW (May 1982). "Is oxytocin an ovarian hormone?". Nature 297 (5863): 225–7. doi:10.1038/297225a0. PMID 7078636.
- Wathes DC, Swann RW, Pickering BT, Porter DG, Hull MG, Drife JO (August 1982). "Neurohypophysial hormones in the human ovary". Lancet 2 (8295): 410–2. doi:10.1016/S0140-6736(82)90441-X. PMID 6124806.
- Guldenaar SE, Pickering BT (1985). "Immunocytochemical evidence for the presence of oxytocin in rat testis". Cell Tissue Res. 240 (2): 485–7. doi:10.1007/BF00222364. PMID 3995564.
- Gauquelin G, Geelen G, Louis F, Allevard AM, Meunier C, Cuisinaud G, Benjanet S, Seidah NG, Chretien M, Legros JJ (1983). "Presence of vasopressin, oxytocin and neurophysin in the retina of mammals, effect of light and darkness, comparison with the neuropeptide content of the neurohypophysis and the pineal gland". Peptides 4 (4): 509–15. doi:10.1016/0196-9781(83)90056-6. PMID 6647119.
- Ang VT, Jenkins JS (April 1984). "Neurohypophysial hormones in the adrenal medulla". J. Clin. Endocrinol. Metab. 58 (4): 688–91. doi:10.1210/jcem-58-4-688. PMID 6699132.
- Fields PA, Eldridge RK, Fuchs AR, Roberts RF, Fields MJ (April 1983). "Human placental and bovine corpora luteal oxytocin". Endocrinology 112 (4): 1544–6. doi:10.1210/endo-112-4-1544. PMID 6832059.
- Geenen V, Legros JJ, Franchimont P, Baudrihaye M, Defresne MP, Boniver J (April 1986). "The neuroendocrine thymus: coexistence of oxytocin and neurophysin in the human thymus". Science 232 (4749): 508–11. doi:10.1126/science.3961493. PMID 3961493.
- Amico JA, Finn FM, Haldar J (November 1988). "Oxytocin and vasopressin are present in human and rat pancreas". Am. J. Med. Sci. 296 (5): 303–7. doi:10.1097/00000441-198811000-00003. PMID 3195625.
- Kukucka Mark A, Misra Hara P (1992). "HPLC determination of an oxytocin-like peptide produced by isolated guinea pig Leydig cells: stimulation by ascorbate". Arch. Androl. 29 (2): 185–90. doi:10.3109/01485019208987723. PMID 1456839.
- Venkatesh B, Si-Hoe SL, Murphy D, Brenner S (November 1997). "Transgenic rats reveal functional conservation of regulatory controls between the Fugu isotocin and rat oxytocin genes". Proceedings of the National Academy of Sciences of the United States of America 94 (23): 12462–6. doi:10.1073/pnas.94.23.12462. PMC 25001. PMID 9356472.
- Grillon C, Krimsky M, Charney DR, Vytal K, Ernst M, Cornwell B (2013). "Oxytocin increases anxiety to unpredictable threat". Mol. Psychiatry 18 (9): 958–60. doi:10.1038/mp.2012.156. PMC 3930442. PMID 23147382.
- Guzmán YF, Tronson NC, Jovasevic V, Sato K, Guedea AL, Mizukami H, Nishimori K, Radulovic J (2013). "Fear-enhancing effects of septal oxytocin receptors". Nat. Neurosci. 16 (9): 1185–7. doi:10.1038/nn.3465. PMC 3758455. PMID 23872596.
- Theodoridou A, Penton-Voak IS, Rowe AC (2013). "A direct examination of the effect of intranasal administration of oxytocin on approach-avoidance motor responses to emotional stimuli". PLoS ONE 8 (2): e58113. doi:10.1371/journal.pone.0058113. PMC 3585234. PMID 23469148.
- Fischer-Shofty M, Shamay-Tsoory SG, Harari H, Levkovitz Y (2010). "The effect of intranasal administration of oxytocin on fear recognition". Neuropsychologia 48 (1): 179–84. doi:10.1016/j.neuropsychologia.2009.09.003. PMID 19747930.
- Theodoridou A, Penton-Voak IS, Rowe AC (2013). "A direct examination of the effect of intranasal administration of oxytocin on approach-avoidance motor responses to emotional stimuli". PLoS ONE 8 (2): e58113. doi:10.1371/journal.pone.0058113. PMC 3585234. PMID 23469148.
- Lischke A, Gamer M, Berger C, Grossmann A, Hauenstein K, Heinrichs M, Herpertz SC, Domes G (2012). "Oxytocin increases amygdala reactivity to threatening scenes in females". Psychoneuroendocrinology 37 (9): 1431–8. doi:10.1016/j.psyneuen.2012.01.011. PMID 22365820.
- Dale HH (May 1906). "On some physiological actions of ergot". J. Physiol. (Lond.) 34 (3): 163–206. PMC 1465771. PMID 16992821.
- Ott I, Scott JC. The Action of Infundibulum upon Mammary Secretion (1910). Proc Soc Exp Biol. 8: 48–49.
- Schafer EA, Mackenzie K (July 1911). "The Action of Animal Extracts on Milk Secretion". Proceedings of the Royal Society B 84 (568): 16–22. doi:10.1098/rspb.1911.0042.
- du Vigneaud V, Ressler C, Trippett S (December 1953). "The sequence of amino acids in oxytocin, with a proposal for the structure of oxytocin". J. Biol. Chem. 205 (2): 949–57. PMID 13129273.
- du Vigneaud V, Ressler C, Swan JM, Roberts CW, Katsoyannis PG, Gordon S (1953). "The synthesis of an octapeptide amide with the hormonal activity of oxytocin". J. Am. Chem. Soc. 75 (19): 4879–80. doi:10.1021/ja01115a553.
- du Vigneaud V, Ressler C, Swan JM, Roberts CW, Katsoyannis PG (June 1954). "The synthesis of oxytocin". J. Am. Chem. Soc. 76 (12): 3115–3121. doi:10.1021/ja01641a004.
- du Vigneaud V, Ressler C, Swan JM, Roberts CW, Katsoyannis PG (1954). "The Synthesis of Oxytocin1". Journal of the American Chemical Society 76 (12): 3115–3121. doi:10.1021/ja01641a004.
- du Vigneaud V (1956). "Trail of sulfur research: from insulin to oxytocin". Science 123 (3205): 967–74. doi:10.1126/science.123.3205.967. PMID 13324123.
- Lee HJ, Macbeth AH, Pagani JH, Young WS (June 2009). "Oxytocin: the Great Facilitator of Life". Progress in Neurobiology 88 (2): 127–51. doi:10.1016/j.pneurobio.2009.04.001. PMC 2689929. PMID 19482229.
- Caldwell HK, Young WS III (2006). "Oxytocin and Vasopressin: Genetics and Behavioral Implications". In Abel L, Lim R. Handbook of neurochemistry and molecular neurobiology. Berlin: Springer. pp. 573–607. ISBN 0-387-30348-0.
- Trust, Morality and Oxytocin, a TED talk by Paul J. Zak (July 2011)
- Molecular neurobiology of social bonding: Implications for autism spectrum disorders, a National Institutes of Health lecture by Larry Young (January 4, 2010)
- The science of love: I get a kick out of you from The Economist (February 12, 2004)