长期迷走神经电刺激对肥胖鼠摄食和体重的影响

目的观察膈下迷走神经刺激(vagal nerves stimulation,VNS)对肥胖鼠摄食、体重、摄食神经肽的影响。方法将18只雄性营养性肥胖鼠(dietary induced obesity,DIO)随机分3组:对照组、假手术组、VNS组。VNS组大鼠体内植入自主研发的闭环芯片并高脂饲养90天,芯片电刺激膈下迷走神经;假手术组体内植入不工作的芯片;对照组不做手术。术后每天测量所有动物体重、日进食量。90天后处死所有动物,分离并称重双侧附睾脂肪垫。反转录PCR法(RT-PCR)半定量检测摄食神经肽:重组人刺鼠色蛋白相关蛋白(AgRP)、神经肽Y(NPY)、可卡因-苯丙胺调节转录因子编码的肽(CART)、阿片促黑色素原(POMC)的含量。结果 VNS组大鼠体重增加量[(124.3±15.5)g vs.(263.1±16.8)g,P=0.013],总摄食量[(1998.7±37.2)g vs.(3312.6±40.9)g,P=0.021]以及附睾脂肪垫重量[(15.9±2.3)g vs.(22.7±2.6)g,P=0.035]明显低于假手术组。VNS组大鼠下丘脑促摄食神经肽AgRP(P=0.027)、NPY的含量(P=0.019)低于假手术组,而抑制摄食的神经肽POMC高于假手术组(P=0.011)。结论 膈下迷走神经电刺激可显著减少大鼠摄食量,减轻体重。

Effect of Long-term Vagal Stimulation on Food Intake and Body Weight of Dietary-induce Obesity in Rats

Objective To assess the effects of vagal nerve stimulation(VNS) on the food intake,body weight and level of ingestion neuropeptides in obesity rats. Methods Eighteen male dietary-induced obesity(DIO) rats were randomly divided into control,pseudo-surgery and VNS groups.In the VNS group,all the animals underwent implantation of a vagal nerve stimulator at the gastro-esophogeal junction and received high-fat dietary for 90 days at the mean time of the stimulation.Pseudo-surgery group underwent the same procedure but without implating the stimulator.And the control received no surgery.After the surgery,the body weight and daily food intake were measured every day,and we killed the animals on day 90 to separate and weigh the bilateral epididymal fat pads.RT-PCR was employed to determined the levels of ingestion neuropeptides,AgRP,NPY,CART,and POMC.Results VNS group showed significantly lower body weight gain [(124.3±15.5) g vs.(263.1±16.8) g,P=0.013],weight of epididymal fat pad [(15.9±2.3) g vs.(22.7±2.6) g,P=0.035],and food consumption [(1998.7±37.2) g vs.(3312.6±40.9) g,P=0.021];VNS group showed significantly lower level of AgRP(P=0.027) and NPY(P=0.019),but higher level of POMC(P=0.011) than the pseudo-surgery group. Conclusion VNS can significantly reduce the food intake of obesity rats and thus decrease body weight.