电针大鼠“四白”穴和胃扩张传入信息在孤束核的汇聚——c-fos表达的研究

目的:探讨电针足阳明经“四白”穴和胃扩张刺激诱导大鼠孤束核(NTS)的原癌基因c -fos表达及意义。方法:将SD大鼠随机分为4组:电针“四白”穴组、电针“四白”穴旁开0 .5cm组、胃扩张模型组和空白对照组。采用免疫组织化学方法观察c- fos在孤束核的表达。结果:电针“四白”穴组和胃扩张模型组孤束核内Fos样免疫反应(FLI)阳性神经元均主要分布于内侧亚核,以延髓的中尾段分布较多;电针“四白”穴组在内侧亚核内FLI神经元数目与胃扩张模型组比较无明显差异(P >0 .0 5 ) ,与“四白”穴旁开组比较,差异有非常显著性意义(P <0 .0 1 )。结论:电针“四白”穴和胃扩张刺激的感觉传入可能在孤束核发生汇聚、整合,是针刺“四白”穴调节胃功能的中枢途径之一。

Convergence of Information from Electroacupuncture of "Sibai"(ST 2) and Gastric Distention on Rat Nucleus of the Solitary Tract Shown by c-fos Expression

Objective: To observe the relationship among Nucleus of the Solitary Tract (NTS), “Sibai” (ST 2) and stomach in the rat. Methods: Thirty-two SD rats were randomized into normal control group, “Sibai” group, non-acupoint (0.5 cm beside ST-2) group and gastric-distention group with 8 cases being in each group. EA (4 Hz, 50 Hz, 20 V) was applied to “Sibai” (ST 2) and non-acupoint for 20 min. Gastric distention was conducted for 20 min by using a balloon filled with 5 mL of normal saline. The sections of medulla oblongata tissues containing NTS were stained with immunohistochemical technique (ABC method) for displaying expression of c-fos. Results: Microscopic observation showed that fos-like immunoreaction (IR) positive cells mainly presented in medial subnucleus of NTS (mnTS), middle and caudal medulla oblongata. The IR-positive cells of mnTS in normal control, “Sibai”, non-acupoint and gastric-distention groups were 5.50 ±2.30, 32.03±7.35, 14.76±3.06 and 31.03±3.60 respectively. The IR-positive cells of “Sibai”, non-acupoint and gastric-distention groups were significantly more than those of normal control group (P<0.01), those of “Sibai” group were significantly more than those of non-acupoint group; and no significant difference was found between “Sibai” and gastric distention groups (P>0.05). Conclusion: Results display that the sensatory information from EA of “Sibai” (ST 2) and gastric distention may converge on NTS, suggesting a relatively specific connection between Sibai and stomach.