Adrenomedullin modulates COX-2 and HGF expression in reserpine-injuried gastric mucosa in the rat.

Here we show the increased hepatocyte growth factor (HGF) and cyclooxygenase-2 (COX-2) expression in gastric mucosa of rats which have developed a reserpine-induced ulcer. Such an increase of HGF and COX-2 expression was blunted in rats pretreated with adrenomedullin. Pretreatment with adrenomedullin and the adrenomedullin22-52 fragment did not result in changes of HGF and COX-2 expression, compared to the reserpine and adrenomedullin treated group. Pretreatment with adrenomedullin and the calcitonin gene-related peptide8-37 fragment (CGRP8-37) increased HGF and COX-2 expression, compared to the reserpine and adrenomedullin treated group. Our results suggest that the inhibitory effect of adrenomedullin on the expression of HGF and COX-2 is mediated by CGRP receptors.