Abstract
With low doses of caerulein given intravenously or subcutaneously, vomiting could be induced. Although vomiting was not inhibited by chlorpromazine or atropine, a strong inhibition was evident when metoclopramide was administered subcutaneously at such doses as inhibit vomiting induced by oral administration of CuSO4. Even high doses of caerulein failed to induce vomiting in vagotomized and splanchnicotomized dogs. With intraventricular injection, no effects were observed on blood pressure, respiration or gastrointestinal motility, and vomiting was not induced. Therefore, a reflex mechanism appears to be involved in vomiting induced by caerulein. It is suggested that the actions of caerulein may not be mediated through the central nervous system.
