大鼠急性胃黏膜损伤修复过程中TRPV1的变化及意义

Expression and significance of TRPV1 in gastric mucosal during healing of acute gastric mucosal lesion in rats

目的探讨大鼠急性胃黏膜损伤后修复过程中胃黏膜瞬时受体电位香草酸亚型1(TRPV1)的变化及意义。方法将40只健康Wistar大鼠随机分为正常对照组(NC组)、浸水束缚应激(WIRS)模型组(WIRS组)、WIRS后1 d组(W1d组)、WIRS后3 d组(W3d组),各10只。除NC组外,余30只按WIRS法复制急性胃黏膜损伤模型。于不同时间点观察各组胃黏膜损伤、修复情况,比较胃黏膜损伤指数(UI)、胃组织含水量、胃液pH值,免疫组化和Q-PCR法检测胃黏膜TRPV1平均光密度值及mRNA表达。结果与NC组相比,WIRS组胃黏膜损伤严重,UI、胃组织含水量升高(P<0.05),胃液pH值下降(P<0.05)。与WIRS组相比,W1d组、W3d组UI、胃组织含水量降低(P<0.05),胃液pH值升高(P<0.05);W3d组UI低于W1d组(P<0.05),与NC组差异无统计学意义(P>0.05),胃组织含水量、胃液pH值与W1d组差异无统计学意义(P>0.05),均高于NC组(P<0.05);与NC组相比,WIRS组、W1d组TRPV1平均光密度值及mRNA降低(P<0.05),W1d组低于WIRS组(P<0.05),W3d组高于WIRS组、W1d组(P<0.05),与NC组比较差异无统计学意义(P>0.05)。结论急性胃黏膜损伤后修复过程中胃黏膜TRPV1出现先降低后升高的动态变化,至第3天恢复正常,TRPV1的变化是胃内多种局部因素作用的结果。

Objective To investigate the expression and the significance of TRPV1 in healing of acute gastric mucosal lesion in rats. Methods Forty healthy Wistar rats were randomly divided into normal controlled group （ Group NC, n = 10）, WIRS model group （Group WIRS, n = 10）, 1 d after WIRS group （Group Wld, n = 10） and 3 d after WIRS group （ Group W3d, n = 10）. The model of acute gastric mucosal lesion was established by the WIRS method. The general extent of gastric mucosal injury was observed and assessed using gastric mucosal ulcer index （UI）. Water content in stomach tissue and intragastric pH value were measured, as the expression of TRPV1 mRNA in gastric mucosa was assessed by Real -time Quantitative PCR and immunohistochemistry. Results Compared with Group NC, in Group WIRS there were obvious gastric mncosa injury with significant increases of UI and water content in stomach tissue, and lower intragastric pH （P 〈0. 05）. Compared with Group WIRS, the UI and water contents in stomach tissue in Group Wld and W3d were significantly reduced （P 〈 0. 05 ） , with significantly increase of intragastric pH （P 〈 0. 05 ）. There was no significant difference in UI between Group W3d and Group NC, while it was significantly lower in Group W3d than Group W1 d （ P 〈 0.05 ）. There was no significant difference in water content or gastric pH between Group Wld and W3d, while they were significantly higher in Group W1 d than Group NC （ P 〈 0. 05 ）. Compared with Group NC, the mean density of TRPV1 and expression of TRPV1 mRNA in the gastric mucosa of Group WIRS and Wld were significantly reduced （P 〈 0. 05 ） , while they were significantly lower in Group W1 d than Group WIRS （ P 〈 0.05 ） , and were significantly higher in Group W3d than Group WIRS and W1 d （P 〈 0. 05 ）. Conclusion In the healing process of acute gastric mucosal, the expression of gastric TRPV1 showes a trend from decline to rise and returned to normal after 3 days.