Innervation of the mammalian anterior pituitary: A mini review

Abstract

The mammalian anterior pituitary was not known to be innervated other than by a few autonomic nerve fibers. Recent studies, however, have demonstrated otherwise. A hypothesis of neural-humoral dual regulation of the mammalian anterior pituitary has been postulated based on the following findings: (1) the presence of substantial amounts of nerve fibers in the anterior pituitary of a number of mammalian species; (2) close contact of the nerve fibers with the gland cells, even forming synapses; (3) the nerve fibers originate, as least partly, from the hypothalamus; (4) the nerve fibers respond actively to changes in hormonal levels of the organism; and (5) stimulation of the nerve fibers changes the secretory activities of the gland cells.

Response of Substance P‐Immunoreactive Nerve Fibres in the Anterior Pituitary to Plasma Oestrogen Levels in the Rat

“…Female young adult Sprague-Dawley rats weighing 220-250 g were used. ary has been proposed ( 14). Our previous studies have demon-Ovariectomy and treatments strated a significant increase in CGRP-LI nerve fibres in the anterior pituitary following adrenalectomy in the rat (10).…”

“…The morphological and functional evidence obtained so far strongly suggests that the Experiment 2: Ovariectomy and oestrogen substitution studies nerve fibres directly regulate the activities of the anterior pituitary. Thus, a hypothesis of neural-humoral dual regulation of the Six days after ovariectomy (OVX ), the number of SP-LI nerve mammalian anterior pituitary has been proposed (10,13,14 ). To fibres in the anterior pituitary was found to be markedly increased.…”

Expression pattern of neuronal intermediate filament α-internexin in anterior pituitary gland and related tumors

“…Microscopic evaluation revealed INA expression not only in single cells but also in filament-like processes of the AH resembling axonal structures. Whereas neuronal innervation of animal pituitary is well known [43], investigations focusing on human AH are rare. In a recent study peptidergic nerve fibers were depicted, which arise from the human pituitary stalk, enter the pituitary frontal lobe and frequently forming synapses with endocrine cells [44].…”