Adult

The gland hangs from the floor of the brain bv means of the infundibular stalk

ADENOHYPOPHYSIS Part infundibutaris

Pan neural» (posterior lobe)

Floor of the diencephalon

Pars intermedia of the anterior lobe

NEUROHYPOPHYSIS Infundibular stalk

Pan neural» (posterior lobe)

Floor of the diencephalon

Pars intermedia of the anterior lobe

FIGURE 4-1 Development of the pituitary gland. Reproduced by permission from Langebartel, D. A. (1977): "The Anatomical Primer." University Park Press, Baltimore, Maryland.

In its major action, VP inhibits water diuresis, and OT can also produce this effect. Of interest is the possible precursor status of OT for the formation of CNS-active peptides. Since VP is involved in ACTH secretion, and OT produces MIF and MRF in some species (probably not in higher mammals), then there may be regulatory systems to partition the fates of VP and OT between the formation of releasing factors or other biological products active in the CNS and storage in the terminals of the neurohypophysis. The most significant partition occurs through the distinct signals for the release of each hormone and the relative specificity of receptors. As new actions of OT become apparent in tissues common to males and females, the role of this hormone in males may emerge.

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