Objective: To study the effect of the calcitonin gene-related peptide on the pathogenesis of peptic ulcer. Methods: In this article

the concentrations of calcitonin gene-related peptide in gastric mucosa and peripheral plasma were assessed by radioimmunoassay in 46 patients with peptic ulcer and 15 healthy adults. The relationship between CGRP concentrations in plasma or mucosa and the area of ulcer was examined. Results: The results showed that plasma calcitonin gene-related peptide concentrations were reduced (P < 0.01 compared with normal) in the ulcer groups. Plasma CGRP concentrations in active stages of ulcer were significantly less than those in normal subjects

and those in healing stages were significantly greater than those in normal subjects (P < 0.01)

and those in scarring stages of ulcer were gradually restored .CGRP level of ulcer mucosa was different from CGRP level of its normal mucosa and the mucosa of control groups (2.5289 2.576 pmol/L/g; 7.374 6.7045 pmol/L/g

P < 0.01; and 5.4515 1.7784pmol/L/g

P < 0.01).There was no correlation between the calcitonin gene-related peptide concentrations in mucosal specimens from ulcer margins and the area of ulcer (r = 0.2526

P > 0.05). Conclusion: Our studies suggest that CGRP might participate in a restoration mechanism of ulcer; and locally reduced calcitonin gene-related peptide may be an important factor contributing to the pathogenesis of peptic ulcer.