Inhibition of suckling in weaning-age rats: A possible serotonergic mechanism.

Publisher Website
Google Scholar
Abstract
The nature, development and specificity of serotonergic involvement in the control of suckling behavior in rat pups from 10-35 days of age were studied. During development, suckling normally declines after 10 days and is abandoned after 30 days. Methysergide, a serotonin (5-HT) receptor blocker, reinstated suckling behavior in pups 15 days of age and older but had no effect on the suckling of 10 day old pups. Quipazine, a 5-HT receptor agonist, inhibited suckling of pups 10 days of age and older. Methysergide pretreatment blocked the quipazine inhibition of suckling and metergoline, another 5-HT blocker, also stimulated suckling. Fenfluramine, a 5-HT releaser, blocked suckling in deprived pups. A serotonergic inhibitory mechanism may modulate the suckling of weaning-age rats. These pharmacological manipulations of 5-HT appear to alter specific components of suckling behavior involved in its initiation and maintenance but do not appear to alter a general hunger system.