胃袖状切除术对2型糖尿病大鼠肾功能的影响

The effects of sleeve gastrectomy on renal function in type 2 diabetic rats

目的 探讨胃袖状切除术对2型糖尿病大鼠肾功能的影响及其机制.方法 通过腹腔内注射链脲菌素诱导SD大鼠糖尿病模型,共有36只大鼠诱导成功.选取血糖水平居中的30只大鼠随机分成3组（血糖17.88～23.65 mmol/L,平均20.32 mmol/L）：胃袖状切除组、假手术组及对照组,每组10只.术后检测大鼠一般情况、血脂、肌酐,取大鼠24 h尿液检测24 h尿微量清蛋白排泄率.行血、尿肌酐检测计算肾小球滤过率,实验结束取肾称重并对肾小球进行病理学检查,PAS染色观察肾小球系膜扩张情况,计算系膜扩张率.通过免疫组化技术检测肾小球足细胞突触极蛋白表达率,进一步明确胃袖状切除手术对糖尿病大鼠肾功能的影响的机制.检测数据的组间比较采用单因素方差分析,组间两两比较采用t检验.结果 胃袖状切除组大鼠术后死亡1只,另两组大鼠无死亡.胃袖状切除组大鼠肾小球滤过率[（8.44 ±2.10） ml·g^-1·d^-1]、24 h尿蛋白排泄率[（36.04±11.10） mg/d]、血脂[总胆固醇（1.66±0.23） mmol/L,甘油三酯（1.25±0.17）mmol/L]、肾脏质量[（1.61±0.06）g]、肾小球系膜扩张率[（6.14±1.50）％]和足细胞突触极蛋白表达率[（20.44±2.99）％]均优于假手术组[（15.05 ±3.01）ml·g^-1·d^-1、（57.01±11.34） mg/d、（2.15±0.29） mmol/L、（1.65±0.23） mmol/L、（1.93±0.07）g、（11.32±2.09）％、（10.34±1.43）％]和对照组[（14.79±2.38）ml·g^-1·d^-1、（62.71±16.46） mg/d、（2.23±0.21） mmol/L、（1.59±0.20） mmol/L、（1.91±0.06）g、（10.82±1.79）％、（11.13±2.43）％]（t=0.781 ～5.025,P值均＜0.05）.结论 胃袖状切除手术可明显改善2型糖尿病大鼠模型的肾功能,手术可能通过改善肾小球系膜扩张及保护肾小球足细胞来改善肾功能.

Objective To examine the renal function changes and mechanisms on rats with diabetes through a sleeve gastrectomy operation.Methods Thirty-six rats were induced diabetes through injection of streptozotocin（STZ）,and 30 of these diabetic rats that blood glucose levels at the midrange（blood sugar 17.88-23.65 mmol/L,mean：20.32 mmol/L） were randomly assigned to the sleeve gastrectomy group,Sham-operation group and control group.The serum creatinine,lipid parameters were measured postoperatively.The 24 h urine volume obtained and urine albumin excretion rate （UAER） was calculated.Serum and urinary creatinine were examined and glomerular filtration rate （GFR） was counted.Kidney sections were stained with periodic acid-Schiff,and then the index of mesangial expansion was determined.The expression of synaptopodin for podocytes was also performed through the immunohistochemical procedure.A one-way ANOVA and t-test were performed to evaluate differences between groups and each other.Results Only one rat of SG group died after operation.The GFR （（8.44±2.10）ml · g^-1 · d^-1）,24 h UAER（（36.04±11.10） mg/d）,plasma lipids level（total cholesterol（1.66±0.23） mmol/L,triglycerides （1.25 ± 0.17） mmol/L）,kidney weight （（1.61 ± 0.06） g）,the index of mesangial expansion（（6.14 ± 1.50）%） and synaptopodin expression （（20.44 ± 2.99）%） were improved in the SG group compared with the sham-operation group（（15.05 ± 3.01）ml·g^-1·d^-1/d,（2.23±0.21）mmol/L,（1.59 ± 0.20）mmol/L,（1.91 ± 0.06）g,（10.82 ±1.79）%,（11.13 ±2.43）%） （t =0.781-5.025,all P 〈 0.05）.Conclusion The sleeve gastrectomy procedure can improve the renal function in a diabetes rat model may be through protecting the podocytes function and preventing the mesangial expansion of glomeruli.