谷氨酰胺对2型糖尿病大鼠血糖和胰岛素抵抗的影响吴亚谋刘月江胡柳夏江燕景亮[摘要]目的观察L-谷氨酰胺对2型糖尿病大鼠血糖变化和胰岛素抵抗的影响并探讨可能机制。方法SD雄性大鼠47只，按随机数字表法分为4组：空白对照组（C组）10只、谷氨酰胺(glutamine，Gln)组（Gln组）10只、2型糖尿病组（DM组）12只、2型糖尿病+谷氨酰胺组(DM+Gln组)15只。实验动物分组饲养，2型糖尿病大鼠模型制作成功并稳定后予以Gln(1g·kg-1·d-1)继续灌胃3周，分别检测各组大鼠第1、6、9周末空腹血糖（fastingbloodglucose,FBG）值和空腹血胰岛素（fastinginsulin，FNS）值并计算胰岛素抵抗值（homeostasismodelassessment-insulinresistanceindex，HOMA-IR）。于第9周末取大鼠腓肠肌检测肌细胞葡萄糖转移蛋白4(glucosetransportertype4，GLUT4)向细胞膜转位量和细胞内葡萄糖转移蛋白4信使RNA(GLUT4mRNA)表达量。结果在第6周末，DM组和DM+Gln组大鼠FBG分别升高为(16.3±3.7)mmol/L和(15.9±4.8)mmol/L，分别与C组(5.9±1.4)mmol/L和Gln组(5.9±0.9)mmol/L相比差异有统计学意义（P＜0.05）。同时间点DM组和DM+GIn组HOMA-IR分别升高为(4.1±0.5)和(4.0±0.6)，分别与C组(3.4±0.3)和Gln组(3.3±0.4)相比差异有统计学意义（P＜0.05）；在第9周末，DM+Gln组FBG(15±9)mmol/L明显低于DM组(24±12)mmol/L(P＜0.05)，DM+Gln组HOMA-IR(3.0±0.6)明显低于DM组(3.7±0.4)(P＜0.05)，同时间点C组(3.3±0.4)和Gln组(3.2±0.5)也明显低于DM组(P＜0.05)；4组之间GLUT4蛋白膜转位量和GLUT4mRNA差异无统计学意义（P＞0.05）；结论对2型糖尿病大鼠连续投入Gln3周可以增强胰岛素敏感性，维持血糖相对稳定，但其机制与葡萄糖转运体基因表达和蛋白转运无关。L-谷氨酰胺；2型糖尿病；空腹血糖；胰岛素抵抗；葡萄糖转移蛋白4；葡萄糖转移蛋白4信使RNAEffectofglutamineonbloodglucoseandinsulinresistanceintype2diabetesratsWUYa-mouLIUYue-jiangHULiuXIAJiang-yanJINGLiangDepartmentofAnesthesiology,SoutheastUniversityAffiliatedZhong-DaHospital,Nanjing210009,ChinaObjectiveToobservetheeffectofglutamine(Gln)onbloodglucoseandinsulinresistanceintype2diabetesratsandtoexplorethepossiblemechanism.MethodsForty-sevenhealthySDmaleratswererandomlydividedinto4groups:Controlgroup(n=10),Glngroup(n=10),Type2Diabetesgroup(n=12)andGlnandType2Diabetesgroup(n=15).AftersetupoftheType2Diabetesratmodelssuccessfully,Gln(1g·kg-1·d-1)wasadministeredorallybygavageforthreeweekscontinuously.fastingbloodglucose(FBG)andfastinginsulin(FNS)weremeasuredattheendofWeek1st,6thand9th,respectively.Thenhomeostasismodelassessment-insulinresistanceindex(HOMA-IR)wascalculatedbasedonFBGandFNS.Attheendofweek9th,mRNAandproteinexpressionofglucosetransportertype4(GLUT4)weremeasuredbyreversetranscriptivepolymerasechainreaction(RT-PCR)andWB,respectively.ResultsAttheendofthesixthweek,FBGwassignificantlyincreasedto(16.7±3.5)mmol/Land(15.9±4.8)mmol/LinDMandDM+Glngroups,andthereisnodifferencebetweenthesetwogroups.However,comparedwithCgroup(5.9±1.4)mmol/LandGlngroup(5.9±0.9)mmol/L,FBGwashighlyraisedinDMandDM+Glngroups(P＜0.05).Meanwhile,FNSwassignificantlyincreasedto(4.1±0.5)and(4.0±0.6)inDMandDM+Glngroups,comparedwithCgroup(3.4±0.3)andGingroup(33±0.4),FBGwashighlyraisedinDMandDM+Glngroups(P＜0.05).Attheendof9thweek,FBGinDMgroup(24.5±11.8)mmol/LwassignificantlyhigherthanthatinDM+Gln(15.2±9.6)rmtmol/L,HOMA-IRinDMgroup(3.7±0.4)wassignificantlyhigherthanthatinDM+Glngroup(3.0±0.6)(P＜0.05),Meanwhile,HOMA-IRinCgroup(3.3±0.4)andGlngroup(3.2±0.5)weresignificantlylowerthanthatinDMgroup(P＜0.05).TherewerenosignificantdifferentinmRNAandproteinofGLUT4amongfourgroups(P＞0.05).ConclusionContinuallyoralofGlncansta...
