STIMULATION OF THE SUPRAOPTICOHYPOPHYSIAL TRACT IN THE RAT DURING SUCKLING: FAILURE TO ALTER THE INHERENT PERIODICITY OF REFLEX OXYTOCIN RELEASE

Publisher Website
Google Scholar
Abstract
A.R.C. Institute of Animal Physiology, Babraham, Cambridge, CB2 4AT (Received 14 April 1975) One explanation for the intermittent milk ejection (ME) in the rat is that the activation of paraventricular (PV) and supraoptic (SO) cells during oxytocin release (Wakerley & Lincoln, 1973; Lincoln & Wakerley, 1974) causes a temporary block of further transmission of the suckling stimulus to the hypothalamus by inhibitory feedback on to afferent pathways of the milk-ejection reflex. Since oxytocin injections have no effect on endogenous hormone release (Lincoln, 1974), this feedback is unlikely to be humorally mediated. However, there still remains the possibility of a direct neural feedback, especially since PV and SO cells appear to possess recurrent collateral axons (Koizumi & Yamashita, 1972). In the present study we investigated the existence of such a neural feedback by attempting to alter the inherent periodicity of reflex oxytocin release with stimulation of the supraopticohypophysial (SOH) tract. Lactating

This publication has 0 references indexed in Scilit: