Transient prevention of ethanol-induced gastric lesion by capsaicin due torelease of endogenous calcitonin gene-related peptide in rats

Pre-exposure of the rat gastric mucosa to capsaicin reduced the mucosal les ion by 50% ethanol to 1/4. Treatment with an antagonist of calcitonin gene- related peptide (CGRP), CGR-P (8 - 37), nullified the effect of capsaicin. During constant perfusion of the gastric lumen with physiological saline pepstatin, the CGRP level was not increased by 50% ethanol, but it showed a peak (802.5 +/- 145.7 pg/2 min) after 1.6 mM capsaicin. Four minutes after capsaicin, the CGRP level was kept at a high level and the gastric lesion was markedly reduced by re-exposure of the mucosa to 50% ethanol. At 20 - 3 0 min after capsaicin, the CGRP levels returned to the resting level and th e reddened area by 50% ethanol was not reduced. It was concluded that capsa icin transiently prevented the mucosal lesion through CGRP release.