Inhibitory effects of intrahypothalamic injection of calcitonin on TRH-stimulated gastric acid secretion in rats.

Effects of the peripheral and central administration of porcine (PCT) and salmon (SCT) calcitonin on the gastric acid secretion stimulated by various secretagogues were studied in the perfused stomach of anaesthetized rats. The intraperitoneal administration of PCT and SCT inhibited gastric acid secretion stimulated by thyrotropin-releasing hormone (TRH) and 2-deoxy-D-glucose, but neither bethanechol nor tetragastrin. The intracerebroventricular PCT and SCT blocked TRH-induced acid secretion. The intrahypothalamic injection of PCT and SCT reduced the acid secretion stimulated by the intrahypothalamic administration of TRH. The present study indicates that PCT and SCT may in part suppress gastric acid secretion due to an interaction with TRH in the hypothalamus.