Calcitonin gene-related peptide acts within the central nervous system to inhibit gastric acid secretion.

The central nervous system effect of calcitonin gene-related peptide (CGRP) on gastric acid secretion was studied in conscious freely moving rats. CGRP (220 fmol to 2.2 nmol) injected into the lateral cerebral ventricle or intravenously inhibited gastric acid secretion. Intravenous passive immunization with CGRP antiserum prevented the inhibitory effect of CGRP following intravenous but not intracerebroventricular administration. Adrenalectomy and noradrenergic blockade with bretylium tosylate did not significantly alter the inhibitory action of CGRP given intracerebroventricularly on gastric secretion. These studies indicate that CGRP acts within the central nervous system to potently decrease gastric acid secretion by mechanism(s) not dependent on intact sympathetic nervous function.