Experimental Study on Chronic Stress in Pathogenesis of Chronic Gastritis

Objective To study the possible effects of chronic stress on the pathogenisis of chronic gastritis by observing the changes of gastric mucosa in rats.Methods Seventy-five male Sprague dawley(SD)rats were randomly divided into two groups:chronic stress group(CS group,n=50)and normal control(n=25).CS group underwent water immersion restraint stress,1 hour daily,for 21 days,and the control didn't do any.Observation indexes were as following:(1)changes of bodyweight(BW)and food intake after chronic stress;(2)the levels of monoamine transmitters and related metabolites such as 5-hydroxytryptamine(5-HT),5-hydroxyindoleacetic acid(5-HIAA),noradrenaline(NA),3-methoxy-4-hydroxyphenyl glycol(MHPG),dopamine(DA)and homovanillic acid(HVA),in cerebrospinal fluid after chronic stress;(3)the pathologic changes of gastric mucosa after chronic stress;(4)the measurement of gastric emptying velocity by phenol red test following the test.Results(1)Before chronic stress,there was no significant difference in BW and food intake between two groups,but after it,BW and food intake were significantly lower in CS group than in control(P0.001,P0.01,respectively);(2)The contents of 5-HT,5-HIAA and MHPG of CS group were significantly lower than those of control(P0.001),while the levels of DA,NA and HVA were higher,but without any significant difference between the two(P0.05);(3)General observations were as following:in CS group,spots of erosion were noted in the gastric mucosa in 7 rats,sheets of congestion in 13,no obvious changes in 23;in the control,mild sheets of congestion were seen in 2 rats,no obvious changes in 23(P0.001);Under light microscope,in CS group,chronic atrophic changes occurred in 1 rat,and chronic superficial inflammation in 49 rats;in the control,mild chronic superficial inflammation occurred in 3 rats,and 22 had normal gastric mucosa(P0.001);(4)The gastric residual phenol red rate of CS group was significantly higher than that of the control(P0.05).Conclusion Chronic stress can cause the changes of chronic inflammation of gastric mucosa in rats.