[Effect of losartan on portal hypertensive gastropathy in rats].

Objective: To determine the effect of angiotensin II receptor 1 antagonist losartan on portal hypertensive gastropathy (PHG) in rats and its mechanism.

Methods: Forty-eight Sprague-Dawley rats were randomly divided into 4 groups: a sham-operated group, a model group, a treatment group, and a prevention group. The partial portal vein and left suprarenal vein of rats were ligated to develop PHG. Portal vein pressure (PVP), the level of angiotensin IIin blood, gastric injury index(GI), and pathological diagnosis integral(PI) were measured. In situ hybridization was used to determine the expression and immunolocalization of angiotensin II receptor 1 in rat stomach wall.

Results: PVP, GI, and PI of the treatment group and the prevention group were evidently reduced (P<0.01), and the level of angiotensin IIin blood increased obviously. The expression of angiotensin II receptor 1 was negative in the control group, increased significantly in the model group, and decreased significantly in the treatment group and the prevention group.

Conclusion: The expression of angiotensin II receptor 1 elevates in portal hypertensive gastropathy. Losartan can reduce PVP, inhibit the activation of angiotensin II receptor 1 in gastric submucous layer, and has therapeutic effect on PHG.