User:JLB1117/anatomy and connectivity section: Difference between revisions
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
The area postrema is a small protuberance found at the inferoposterior limit of the [[fourth ventricle]]. Specialized [[ependymal]] cells are found within the area postrema. These specialized ependymal cells differ slightly from the majority of ependymal cells (ependymocytes) forming a unicellular epithelium lining of the ventricles and [[central canal]]. The area postrema is separated from the vagal triangle by the funiculus separans, a thin semitransparent ridge. The vagal triangle overlies the [[dorsal vagal nucleus]] and it situated on the caudal end of the [[rhomboid fossa]] or 'floor' of the fourth ventricle. The area postrema is situated just before the [[obex]], the inferior apex of the caudal ventricular floor. Both the funiculus separans and area postrema have a similar thick ependyma-containing tanycyte covering. [[Ependyma]] and [[tanycytes]] can participate in transport of neurochemicals into and out of the [[cerebrospinal fluid]] from its cells or adjacent neurons, glia or vessels. Epednyma and tanycytes may also participate in chemoreception. The eminence of the area postrema is considered a [[circumventricular organ]] because its endothelial cells do not contain tight junctions, which allows for free exchange of molecules between blood and brain tissue. This unique breakdown in the [[blood-brain barrier]] is partially compensated for by the presence of a tanycyte barrier. |
The area postrema is a small protuberance found at the inferoposterior limit of the [[fourth ventricle]]. Specialized [[ependymal]] cells are found within the area postrema. These specialized ependymal cells differ slightly from the majority of ependymal cells (ependymocytes) forming a unicellular epithelium lining of the ventricles and [[central canal]]. The area postrema is separated from the vagal triangle by the funiculus separans, a thin semitransparent ridge. The vagal triangle overlies the [[dorsal vagal nucleus]] and it situated on the caudal end of the [[rhomboid fossa]] or 'floor' of the fourth ventricle. The area postrema is situated just before the [[obex]], the inferior apex of the caudal ventricular floor. Both the funiculus separans and area postrema have a similar thick ependyma-containing tanycyte covering. [[Ependyma]] and [[tanycytes]] can participate in transport of neurochemicals into and out of the [[cerebrospinal fluid]] from its cells or adjacent neurons, glia or vessels. Epednyma and tanycytes may also participate in chemoreception. The eminence of the area postrema is considered a [[circumventricular organ]] because its endothelial cells do not contain tight junctions, which allows for free exchange of molecules between blood and brain tissue. This unique breakdown in the [[blood-brain barrier]] is partially compensated for by the presence of a tanycyte barrier. <ref>{{cite book |
||
{{cite book |
|||
|editorn-last= Williams, Chairman of the editorial board |
|editorn-last= Williams, Chairman of the editorial board |
||
|editorn-first= Peter L. |
|editorn-first= Peter L. |
||
Line 9: | Line 7: | ||
|year = 1995 |
|year = 1995 |
||
|location= New York |
|location= New York |
||
|isbn = 0443045607}}</ref> Recent research investigating of rat neurology has articulated more specific neural connections between the area postrema and its surrounding central structures. These connections, when considered in the context of the known vagal afferent input and reduced blood-brain barrier of AP, place this structure in a unique position to receive and modulate ascending interoceptive information and to influence autonomic outflow as well. <ref> {{cite journal |
|||
|isbn = 0443045607}} |
|||
{{cite journal |
|||
| last = Shapiro |
| last = Shapiro |
||
| first = Robert E. |
| first = Robert E. |
||
Line 23: | Line 19: | ||
| publisher = Copyright © 1985 Alan R. Liss, Inc. |
| publisher = Copyright © 1985 Alan R. Liss, Inc. |
||
| doi = 10.1002/cne.902340306 |
| doi = 10.1002/cne.902340306 |
||
}} |
}}</ref> |
Revision as of 02:25, 27 October 2009
The area postrema is a small protuberance found at the inferoposterior limit of the fourth ventricle. Specialized ependymal cells are found within the area postrema. These specialized ependymal cells differ slightly from the majority of ependymal cells (ependymocytes) forming a unicellular epithelium lining of the ventricles and central canal. The area postrema is separated from the vagal triangle by the funiculus separans, a thin semitransparent ridge. The vagal triangle overlies the dorsal vagal nucleus and it situated on the caudal end of the rhomboid fossa or 'floor' of the fourth ventricle. The area postrema is situated just before the obex, the inferior apex of the caudal ventricular floor. Both the funiculus separans and area postrema have a similar thick ependyma-containing tanycyte covering. Ependyma and tanycytes can participate in transport of neurochemicals into and out of the cerebrospinal fluid from its cells or adjacent neurons, glia or vessels. Epednyma and tanycytes may also participate in chemoreception. The eminence of the area postrema is considered a circumventricular organ because its endothelial cells do not contain tight junctions, which allows for free exchange of molecules between blood and brain tissue. This unique breakdown in the blood-brain barrier is partially compensated for by the presence of a tanycyte barrier. [1] Recent research investigating of rat neurology has articulated more specific neural connections between the area postrema and its surrounding central structures. These connections, when considered in the context of the known vagal afferent input and reduced blood-brain barrier of AP, place this structure in a unique position to receive and modulate ascending interoceptive information and to influence autonomic outflow as well. [2]
- ^ Gray’s anatomy : the anatomical basis of medicine and surgery (38th ed.). New York: Churchill Livingstone. 1995. ISBN 0443045607.
{{cite book}}
: Unknown parameter|editorn-first=
ignored (help); Unknown parameter|editorn-last=
ignored (help) - ^ Shapiro, Robert E. (1985). "The central neural connections of the area postrema of the rat". The Journal of Comparative Neurology. 234 (3). Copyright © 1985 Alan R. Liss, Inc.: 344–364. doi:10.1002/cne.902340306.
{{cite journal}}
: Unknown parameter|coauthors=
ignored (|author=
suggested) (help)