电针对糖尿病胃轻瘫大鼠胃窦促生长素mRNA、生长激素促分泌素受体mRNA表达的影响

Effect of Electroacupuncture at“Zusanli”(ST 36),etc.on Gastrointestinal Motility and Expression of Ghrelin mRNA and Growth Hormone Secretagogue Receptor mRNA in Diabetic Gastroparesis Rats

目的:观察电针"足三里"等穴对糖尿病胃轻瘫(DGP)大鼠胃肠运动和促生长素(ghrelin)mRNA、生长激素促分泌素受体(GHSR)mRNA表达的影响,探讨电针治疗DGP的可能机制。方法:60只SD大鼠随机分为空白对照组、模型组、电针穴位组、电针非穴组、胃复安对照组,每组12只。采用单次腹腔注射2%链脲佐菌素配合高糖高脂饮食建立DGP大鼠模型。电针穴位组取大鼠"足三里""梁门""三阴交"穴;电针非穴组取"足三里""梁门""三阴交"穴位对照点;胃复安对照组予胃复安药液(1 mL/100g)灌胃。用血糖仪测血糖,尿糖试纸测尿糖。治疗结束后以酚红为标记物,观察大鼠胃排空率及小肠推进率;实时荧光定量多聚核苷酸链式反应法检测大鼠胃窦部ghrelin mRNA、GHSR mRNA的表达。结果:与空白对照组比较,模型组胃排空率及小肠推进率明显降低,ghrelin mRNA、GHSR mRNA表达降低(P<0.01,P<0.05)。与模型组比较,电针穴位组胃排空率及小肠推进率明显升高,ghrelin mRNA、GHSR mRNA表达升高(P<0.05,P<0.01)。与电针非穴位组比较,电针穴位组胃排空率及小肠推进率明显升高(P<0.05,P<0.01)。结论:电针可促进DGP大鼠胃肠运动,其作用机制可能与上调ghrelin mRNA、GHSR mRNA在胃窦部的表达相关。

Objective To observe the effect of electroacupuncture（EA）stimulation of＂Zusanli＂（ST 36）,＂Liangmen＂（ST 21）and＂Sanyinjiao＂（SP 6）on gastrointestinal motility and expression of ghrelin and growth hormone secretagogue receptor（GHSR）mRNA in diabetic gastroparesis（diabetic gastroparesis,DGP）rats,so as to explore its mechanism underlying improvement of diabetic gastroparesis.Methods Sixty SD rats were randomly and equally divided into normal control,model,EA acupoint,EA non-acupoint,medication（metoclopramide）groups（n=12rat/group）.The DGP model was established by intraperitoneal injection of streptozotocin（STZ,55mg/kg,2%）and raised by high-sugar and high-fat fodder irregularly for 8weeks.EA was applied to＂Zusanli＂（ST 36）,＂Liangmen＂（ST 21）and＂Sanyinjiao＂（SP 6）,and non-acupoints（about 5mm lateral to the 3acupoints,respectively）.Those rats of the medication group were given with metoclopramide（1mL/100g）.The blood sugar level was measured by glucometer,and the urine sugar level measured by Tes-Tape [urine glucose test paper].The intestinal propulsion rate（IPR）was identified as ratio of the phenolsulfonphthalein promoting distance and the total length of the small intestine,and the gastric emptying rate（GER）was assessed by gavage of a liquid test meal（1.5mL）containing a nonabsorbable marker（0.5mg/mL of phenol red in 5% glucose solution）and identification after being sacrificed 72 hafter modeling.The expression levels of ghrelin mRNA and GHSR mRNA of gastric antrum tissue were examined by Quantitative real-time PCR.Results In comparison with the normal control group,the blood sugar and urine sugar levels of the model group was significantly increased in the model group（P〈0.01）,while the GER and IPR and the expression level of ghrelin mRNA and GHSR mRNA in the gastric antrum were significantly decreased in the model group（P〈0.01,P〈0.05）.Following EA stimulation of acupoint,the blood sugar and urine sugar levels were obviously down-regulated（P〈0.05）,both GER and IPR,and ghrelin mRNA and GHSR mRNA expression levels in the EA-acupoint group were significantly up-regulated（P〈0.05,P〈0.01）.No significant changes were found in both blood sugar and urine sugar levels,in both GER and IPR,and ghrelin mRNA and GHSR mRNA expression levels of both EA non-acupoint and medication groups after the intervention（P〈0.05）.The GER and IPR were significantly higher in the EA acupoint group than in the EA non-acupoint group（P〈0.05,P〈0.01）.Conclusion EA stimulation of ST 36,ST 21 and SP 6can promote the gastrointestinal motility of DGP rats,which may be closely associated with its effects in up-regulating the expression level of ghrelin mRNA and GHSR mRNA in gastric antrum.