[Role of glucocorticoids and capsaicin-sensitive neurons in gastroprotective effect of ischemic preconditioning].

The study was designed to investigate contribution of glucocorticoid hormones and capsaicin-sensitive neurons to gastroprotective effect of ischemic preconditioning against injury induced by 3.5 h gastric ischemia-reperfusion in rats. The contribution of glucocorticoids was investigated by an inhibition of corticosterone synthesis with metyrapone and adrenalectomy followed by corticosterone replacement. To estimate the role of capsaicin-sensitive neurons we used their desensitization. Gastric ischemia was performed by occlusion of celiac artery in anaesthetized rats. In the control animals gastric ischemic preconditioning (0.5 h ischemia-reperfusion) induced plasma corticosterone rise and attenuated gastric injury caused by 3.5 h ischemia-reperfusion. Both adrenalectomy and desensitization of capsaicin-sensitive neurons by itself aggravated ulcerogenic influence of 3.5 h gastric ischemia-reperfusion. However, only adrenalectomy or metyrapone pretreatment, but not desensitization ofcapsaicin-sensitive neurons prevented gastroprotective effect ofischemic preconditioning. The data suggest that glucocorticoids contribute to gastroprotective effect of ischemic preconditioning even in rats with desensitization of capsaicin-sensitive neurons. The findings support participation of capsaicin-sensitive neurons in gastroprotection against injury caused by prolonged ischemia-reperfusion, but not in gastroprotective effect ofischemic preconditioning.