“合谷”穴和口面部联系的解剖学基础

目的 :用形态学的方法探讨“合谷”穴与口面部的传入联系。方法 :本实验分神经生物素示踪和fos蛋白表达两部分 ,每部分均选用雌性Wistar大鼠 2 4只。将神经束路示踪剂神经生物素分别注射于“合谷”穴区和口面部 ,观察标记纤维在颈段脊髓和低位脑干的分布。电针“合谷”穴和口面部 ,利用免疫组织化学的方法 ,观察其二者的传入信息在颈髓和低位脑干诱导的fos样免疫反应阳性神经元的分布。结果 :“合谷”穴区的初级传入纤维主要止于颈髓 5～ 8节段 ;来自口面部的初级传入纤维主要止于同侧三叉神经脊束核 ,尚有少量分支直接投射至同侧孤束核和网状结构。电针“合谷”穴的传入信息除主要到达颈部脊髓背角外 ,也可到达孤束核和网状结构 ;而电针口面部的传入信息主要抵达同侧三叉神经脊束核、孤束核和网状结构 ,也可影响到颈髓背角等结构的神经元。结论 :“合谷”穴和口面部均与孤束核有着直接或间接的纤维联系 ,这可能是“合谷”穴和口面部联系的形态学基础。

Morphological Study on the Afferent Pathways of "Hegu" Point and Mouth-face Region

Objective: To investigate the afferent pathways and the relationship between mouth-face region and “Hegu” (LI 4) Point. Methods: ① Biotin labeling: Twenty-four adult Wistar rats, divided into facial area and “Hegu” groups, were anesthetized with 1% sodium phentobarbital 40 mg/kg. Neurobiotin (Nb)(2.0%, 20 μL) was injected into the left mouth-face and “Hegu”(LI 4) point regions respectively.72 hours later, these animals under anesthesia were perfused transcardially with saline, then with fixative (1.5% glutaraldehyde and 1.0% paraformaldehyde in 0.1 M sodium phosphate buffer). ② Expression of c-fos: 24 Wistar rats were divided into facial area and “Hegu” groups. Under anesthesia, the left mouth-face and “Hegu” were punctured with acupuncture needles (with two needles being in each point) and stimulated with an electroacupuncture apparatus by setting the stimulating parameters as strength of 5 V, frequency of 100 Hz and duration of 30 min. 1.5～2 hours later, the rats were perfused with the same fixative mentioned above. Spinal cord and lower-brainstem tissues were sliced (30 μm) and then stained with immunohistochemical method. Results: ① Following injection of biotin into facial area, densely labeled fibers were found in the left nucleus of spinal tract of trigeminal nerve (NSTTN) and semilunar ganglion of the trigeminal nerve; light-densely labeled fibers observed in nucleus of the solitary tract (NTS) and reticular formation, and fewer positive fibers seen in the posterior horn of C 1～C 3 of the spinal cord.② The densely labeled fibers from “Hegu” (LI 4) area were found in the posterior horn of C 6, moderate amount of the labeled fibers were seen in C 4～C 5, and fewer seen in cuneate nucleus of the medulla oblongata. ③ After EA stimulation of the left facial area, a large number of fos positive neurons were observed in the ipsilateral NSTTN, moderate number of the labeled cells seen in semilunar ganglion of the trigeminal nerve, NTS and reticular formation of the medulla oblongata, and fewer c-fos positive cells seen in the ipsilateral posterior horn of C 1～C 3 segments. ④ Following EA stimulation of “Hegu”(LI 4), many c-fos positive neurons were observed in the posterior horn of C 4～C 6, and fewer labeling was seen in cuneate nucleus, NTS and reticular formation of the medulla oblongata. Conclusion: Facial area may have a direct connection with NTS, while “Hegu” point has no direct project to NTS, nevertheless, message of EA of “Hegu” may reach NTS by way of secondary afferent neurons, etc. In short, NTS may play an important role in the integration and convergence of information from the facial area and “Hegu” point.