Pituitary stalk

Pituitary stalk

Pituitary stalk not labeled, but is the vertical blue portion.

Basal view of a human brain (Infundibulum labeled third from the top on right)
Details
Latin infundibulum neurohypophyseos
Identifiers
Gray's p.813
MeSH A06.407.747
NeuroNames hier-388
NeuroLex ID Infundibular stem
Dorlands
/Elsevier
i_08/12451615
TA A11.1.00.007
FMA 74635
Anatomical terms of neuroanatomy
Also see infundibulum (disambiguation) for other uses of the term.

The pituitary stalk (also known as the infundibular stalk or simply the infundibulum) is the connection between the hypothalamus and the posterior pituitary. The floor of the third ventricle is prolonged downward as a funnel-shaped recess, the infundibular recess, into the infundibulum, and to the apex of the latter the hypophysis or pituitary is attached.[1]

It passes through the dura mater of the diaphragma sellae as it carries axons from the magnocellular neurosecretory cells of the hypothalamus down to the posterior pituitary where they release their neurohypophysial hormones, oxytocin and vasopressin, into the blood.

This connection is called the hypothalamo-hypophyseal tract or hypothalamo-neurohypophyseal tract.

Compression

It has been thought that the pituitary stalk may become compressed due to suprasellar tumors in the pars tuberalis region, and that the resulting compression may cause hyperprolactinemia.[2] This phenomenon has been described as the stalk effect or pituitary stalk compression syndrome.[2]

However, at least one article suggests that the increase in prolactin in these cases may instead be caused by the tumor's secretion of preprotachykinin A derived tachykinins, substance P, and/or neurokinin A.[2]

Additional images

References

  1. Grey's Anatomy
  2. 2.0 2.1 2.2 Skinner, Donal (March 2009). "Rethinking the Stalk Effect: A New Hypothesis Explaining Suprasellar Tumor-Induced Hyperprolactinemia". Med hypotheses 72 (3): 309–310. doi:10.1016/j.mehy.2008.08.030. PMC 2668659. PMID 19028420. Retrieved June 29, 2012.

External links