脑利钠肽与糖尿病大鼠胃肠排空的关系

摘要

目的：观察糖尿病大鼠血浆、胃窦平滑肌中脑利钠肽（BNP）的变化并探讨其与胃肠排空的关系。方法将大鼠随机分为糖尿病组、单纯肥胖组和对照组，通过高糖高脂饮食结合腹腔注射小剂量链脲佐菌素的方法建立糖尿病大鼠动物模型；用葡萄糖酚红溶液灌胃30 min后处死大鼠，取胃和小肠近、中、远各段留取内容物后使用分光光度计测定胃肠各段酚红残留率；放射免疫法测定血浆N-末端脑利钠肽原（NT-proBNP）的浓度；免疫组化检测胃窦平滑肌内BNP的表达。结果糖尿病组大鼠胃和近段小肠内酚红残留率均多于对照组和单纯肥胖组（P<0.05），而中段和远段小肠酚红残留率均少于对照组和单纯肥胖组（P<0.05）；12周后糖尿病组大鼠血浆NT-proBNP的浓度较对照组和单纯肥胖组显著升高（P<0.05）；胃窦平滑肌层中BNP免疫反应阳性细胞各组间比较无明显差异；糖尿病大鼠血浆NT-proBNP浓度与胃内、近段小肠内酚红残留率呈正相关。结论糖尿病大鼠液体胃肠排空减慢可能与血浆NT-proBNP浓度增加有关。%Objective To investigate the changes of gastric emptying and gastrointestinal transit of liquid in diabetic rats and to study its relationship with brain natriuretic polypeptide (BNP). Methods The male Wistar rats were randomly divided into normal control, simple obesity and diabetes groups, Diabetes rat model was set up by feeding high glucose and high fat diet combined with low dose stretozotocin peritoneal injection. Phenol red recovery in the stomach, proximal, mid and distal small intestine was determined. Plasma level of N-terminal pro-B-type natriuretic peptide (NT-proBNP) was measured by radioimmunoassay for each group. The expression of BNP in gastric was evaluated by immunohistochemistry. Results Phenol red recovery in the stomach and proximal small intestine was increased (P<0.05), while in mid and distal small intestine it was decreased for the diabetic rats when compared with the normal control and simple obesity rats (P<0.05). The plasma NT-proBNP concentration was significantly greater in the diabetic rats compared with that of nor-mal control and simple obesity rats (P<0.05). Immunohistochemistry results showed that the expression of BNP in diabetic rats was not higher than in normal control and simple obesity rats. Conclusion The delayed gastric emptying and gastrointestinal transit of liquid in diabetic rats is related to the increase of plasma NT-proBNP.