Calcitonin gene-related peptide (CGRP) upregulates the restitution of rat gastric mucosa in vitro.

Calcitonin gene-related peptide (CGRP) is a neuropeptide with many significant effects on gastrointestinal function. Among these are gastroprotective effects such as inhibition of acid secretion and increase in gastric mucosal blood flow. To evaluate whether CGRP has a direct protective effect on gastric mucosa, we examined the influence of the peptide on restoration of mucosal integrity following mild damage. Mucosal integrity was assayed by measurement of the transmucosal potential difference of tissue mounted in an Ussing chamber perfusion system. Undamaged mucosa maintained a potential difference of approximately -64 mV in both control tissues and tissues serosally treated with CGRP. Damage was induced by exposure of the gastric mucosa to solutions of 0.5, 1.0, and 2.0 M sodium chloride. Each of the hyperosmolar solutions caused mucosal injury as evidenced by a rapid decrease in PD, with the most concentrated solution causing the greatest decrease and the slowest and least complete recovery. CGRP treatment led to a significantly more complete recovery of PD when injury was caused by 0.5 M but not by either 1.0 or 2.0 M NaCl. We conclude that CGRP is capable of directly enhancing recovery of mucosal integrity after mild but not severe damage of rat gastric mucosa in vitro.