A protective role for calcitonin gene-related peptide in water-immersion stress-induced gastric ulcers in rats

This study investigated the role of endogenous and exogenous calcitonin gene-related peptide (CGRP) in water immersion stress (WIS)-induced gastric ulcers in rats. WIS produced gastric ulcers which were inversely correlated to the decrease in CGRP-like immunoreactivity observed in the whole thickness of the corpus stomach but not in its mucosal layers. Systemic administration of CGRP (100 mu g kg(-1) s.c.) produced a significant decrease in lesion index of WIS-ulcers and this protection was inhibited by functional ablation of afferent neurons induced by capsaicin pretreatment (100 mg kg(-1) s.c, in two days, a week before the experiments). These findings suggest that sensory endogenous CGRP plays a defensive role in WIS-ulcers. (C) 1997 The Italian Pharmacological Society.