Talk:Mammary gland

Do males have mammary glands (as implied by the article) ? -- Vsion 4 July 2005 21:19 (UTC)

Well various sources on google seem to agree. This from the Columbia university press "They are rudimentary in both sexes until the age of puberty when, in response to ovarian hormones, they begin to develop in the female."--Clawed 4 July 2005 22:04 (UTC)

I have read that males can produce breast milk using a certain method. I would say that both men and women have mammary glands, although women's are more developed for the purpose of breastfeeding.

I deleted the following text from the "Structure" subsection, as it has nothing to do with the structure of the mammary gland, and is unsupported by a citation:

"During masturbation many females feel their breasts and nipples. This causes the nipples to become hard and results in a more pleasurable sexual experience."

If someone can find a valid citation for that, then add that back into an appropriate section.

it would be really neat to have a photo of a Monotreme nursing. i have no idea where to find one but would be nice to see

Evolution

"It is believed that the mammary gland is a transformed sweat gland, more closely related to Apocrine sweat glands. There are many theories of how they evolved, but since they do not fossilize well, supporting such theories presents a major difficulty for the researcher. One theory proposes that mammary glands evolved from glands that were used to keep the eggs of early mammals moist."

What the hell do we need the fossilized titties when we have the platypus and the echidna?--94.69.128.204 (talk) 14:19, 14 January 2010 (UTC)

Inactive (Resting) vs. Active (Proliferating) during pregnancy vs. Active (Lactating) after birth

The fellowing three histological differences need to be discussed in the main article and are too complex for me to edit at the current moment. I will add the following information below for others to add in and edit, however, I do not have an online source for this information.

Inactive (Resting) Mammary Gland - the lobes are divided into lobules - there is abundant connective tissue between the lobules, primarily adipose tissue - the glandular elements seen are primarily parts of the duct system: (1) the smallest ducts are lined with simple cuboidal epithelium, and (2) the larger interlobular ducts have stratified epithelium. The lactiferous sinus is lined with stratified cubdoial epithelium while the lactiferous duct is lined with stratified squamous epithelium.

Active (Proliferating) Mammary Gland - During pregnancy there is an increased number of glandular elements and decreased connective tissue elements - The ducts branch and proliferate, and alveoli bud off of the ducts. These alveoli are formed by a simple cuboidal epithelium with myoepithelial cells at the periphery of the alveolus. Contraction of the myoepithelial cells help push the milk secretion into the duct system. - Alveoli show secretory activity in latter half of pregnancy, producing a watery fluid called colostrum immediately after parturition (birth). This colostrum contains large amounts of antibodies that confer passive immunity on the newborn. The antibodies are secreted by lymphocytes and plasma cells (differentiated B-lymphocytes) found in the connective tissue of the pregnant mammary gland.

Active (Lactating) Mammary Gland - After birth, the gland shows little connective tissue - The alveoli are dilated with milk secretions that are rich in sugar, protein, and fat. - The alveoli secrete by both apocrine (lipid component) and merocrine (protein component) secretion. - Milk is controlled by the suckling reflex. A suckling stimulus causes release of oxytocin from the pars nervosa, which causes the myoepithelial cells to contract. This forces the secretory products from the alveoli into the duct system.

Regression of the gland occurs after the cessation of lactation. —Preceding unsigned comment added by 204.152.156.1 (talk) 16:30, 23 October 2010 (UTC)

Embryology

http://www.derm101.com/content/13368, in reference 1 is a better link (as of 1/29/2012) in the discussion of what the evolutionary source of the mamary gland is. Clicking on reference 1 links you to the apocrine chapeter of the on line reference, while the above links you to the embryology. It is more relevant (IMHO) although both are germane. According to the above reference there is NO controversy in the origins of human apocrine glands. They are certainly *not* eccrine (sweat) glands nor are they sebaceous (allthough are related to the latter). I suggest that unless a modern reference can be found to validate that the issue IS controversial that the Histology section be changed to reflect that in humans, milk glands are mistakenly said to be derived from sweat glands. (Contrast this with horse sweat glands which are apparently apocrine). In other words the article seems to be supporting a controversy where no evidence of one is cited.

 Secondly, in the same section: "A mammary gland is a specific type of apocrine gland 

specialized for manufacture of colostrum at the time of parturition." is rubbish. The mammary gland is CLEARLY specialized for manufacture of human milk which can continue for years and decades and the (of secondary importance?) short term manufacture of colostrum (immediately after birth/parturition). How did this ridiculous statement (from the same work as I cite above, but wrong in this context never-the-less) get here? Are there aliens who are not aware of the absurdity now Wikipedia editors?71.31.147.72 (talk) 19:58, 29 January 2012 (UTC)