Effect of Intracerebroventricular Administration of Rat Calcitonin Gene-Related Peptide (CGRP), Human Calcitonin and [Asu1, 7]-Eel Calcitonin on Gastric Acid Secretion in Rats

The effect of intracerebroventricular injection of rat calcitonin gene-related peptide (CGRP), human calcitonin (CT) and [Asu1, 7]-eel CT on the volume and acidity of gastric juice was examined in the pylorus-ligated male rats. These 3 peptides were effective in suppressing both the volume and acidity of secreted gastric juice. Their potency on a molar basis, however, was markedly different;[Asu1, 7]-eel CT was most potent, followed by human CT and finally by rat CGRP. These finding suggest that CGRP could not substitute for [Asu1, 7]-eel or human CT in exerting the suppressive effect of gastric acid secretion.