电针足三里穴对糖尿病胃轻瘫大鼠延髓多巴胺能神经元和星形胶质细胞活性的影响

目的:研究电针足三里穴对糖尿病胃轻瘫大鼠延髓多巴胺能神经元内酪氨酸羟化酶(tyrosine hydroxylase,TH)和星形胶质细胞内胶质原纤维酸性蛋白(Glial Fibrillary Acidic Protein,GFAP)表达的影响。方法:32只实验大鼠分为空白对照(空白)组、糖尿病胃轻瘫模型(模型)组、模型组+电针足三里穴(足三里)组和模型组+电针非经非穴(非经非穴)组(每组8只)。模型制备采用腹腔注射5%四氧嘧啶和熟地灌胃诱导的方法。实验3周后取大鼠延髓进行抗TH和抗GFAP的单一和双重免疫组化染色,观察并记数TH和GFAP在延髓内的表达。结果:与空白组比较,各实验组TH阳性多巴胺能神经元和GFAP阳性星形胶质细胞集中表达于延髓迷走孤束复合体内,有明显的定位特点;高倍镜下观察到TH阳性神经元周围有大量GFAP阳性星形胶质细胞包绕。各组TH和GFAP表达以模型组最高;而足三里组TH阳性多巴胺能神经元数量明显减少(31.3±4.4→16.8±3.2),GFAP阳性产物表达明显降低(113.8±7.6→95.4±8.4),且它们之间有统计学意义(P<0.01);非经非穴组与模型组之间差异没有统计学意义。结论:针刺调节糖尿病胃运动功能障碍大鼠与其调控延髓多巴胺能神经元及其周围的星形胶质细胞功能活动有关。

Effects of Electroacupuncture on Medullary Dopaminergic Neurons andAstrocytes Activation in Diabetic Gastroparesis Model Rats

Objective: To investigate the neural mechanisms of electroacupuncture(EA) effects on the diabetic gastoparesis(DGP),and to investigate the expression of tyrosine hydroxylase(TH) in dopaminergic neurons and glial fibrillary acidic protein(GFAP) in astrocytes in bulbus of diabetic rats.Methods: 32 Rats were divided into 4 groups: control group,DGP model group,DGP plus EA Zusanli acupoint group and DGP plus EA non-acupoint group.DGP model rats were induced by intraperitoneal injection(i.p.)5% alloxan plus poured libosch.After 3 weeks,the expression of TH and GFAP immunoreactivity in bulbus was investigated and calculated by using single or double immunohistochemical method.Results: In the experimental groups,the TH-positive dopaminergic neurons and GFAP-positive astrocytes expressed mainly in the vagal-solitary complex(VSC) of bulbus.Under the high microscope,those dopaminergic neurons were surrounded with their neighboring astrocytes.In the DGP group and EA non-acupoint group,the expression of TH and GFAP immunoreactivity were higher than those in the EA Zusanli groups(P<0.01).Conclusion: EA can improve the gastric motility in DGP model rats.This function may be connected with its regulating the TH-positive dopaminergic neurons and GFAP-positive astrocytes activation in VSC.