Direct inhibition of gastric acid and pepsin secretion by growth-hormone release-inhibiting hormone in cats.

Growth-hormone release-inhibiting hormone (G.H.-R.I.H.) inhibited gastric acid and pepsin secretion in response to pentagastrin and food stimulation in cats. This effect is mediated by a direct action on the parietal and peptic cells. No evidence of a post-inhibitory acid or pepsin secretory rebound was obtained. Thus a compound of hypothalamic origin can exert a direct effect on exocrine secretion. In view of its widespread actions and its presence in relatively high concentrations in various organs apart from the hypothalamus, G.H.-R.I.H. might also be regarded as a factor responsible for local coordination of endocrine and exocrine secretion.