躯体和内脏SP能初级传入神经元的定位研究

本文在后根节和脊髓两个水平对躯体(胫神经)和内脏(膀胱)初级传入系统进行同时定性、定位的研究。对后根节选用两种较敏感的双标技术(HRP结合PAP,Biotin-WGA结合免疫荧光)。结果表明,在后根节中被标记的胫神经和膀胱的初级传入神经元均有一部分同时显示SP样阳性反应。另外在分别切断盆内脏神经和胫神经的两组动物模型上进行脊髓的SP样免疫反应,通过两侧对比,观察到术侧灰质在相当于被切断神经的传入经路及终末区出现SP样反应的“脱落”现象,从而反证出躯体和内脏初级传入纤维中的SP能成分在中枢内的定位分布。本文首次提供了内脏初级传入在中枢内定位与定性相结合的研究结果。

THE DISTRIBUTION OF SP-LIKE VISCERAL AND SOMATIC PRIMARY AFFERENT NEURONS IN THE LUMBOSACRAL DORSAL ROOT GANGLIA AND SPINAL CORD

In order to obtain the information about the central distribution of SP-like visceral (urinary bladder) and somatic (leg) primary afferent fibers, the author used the rat as experimental animal and two experi-meats were carried out. Exp.Ⅰ:Two groups of animal were examined with different combining techniques. One was the combination of HRP retrograde tracing technique and PAP immunohistochemical method, the other was Biotin-WGA tra-cing technique combined with indirect immunofluorescent technique. In these experiments, HRP or Biotin-WGA were injected into the bladder wall and tibial nerve in different animals and then the spinal ganglia were examined for both the tracer and the SP-like substance. The results from both groups showed that both the visceral and somatic primary afferent neurons labelled by the tracers in the spinal ganglia had some small-sized (a few small-medium-sized) nerve cells which gave SP-like positive immunoreaction at the same time. Exp.Ⅱ: Peripheral neurotomy was performed on 21 rats which were divided into two groups. The tibial nerve of 13 rats and the pelvic nerve of 8 rats were transected.The animals survived for 7-60 days before being sacrificed. To observe the change of SP-like active substance in the spinal cord on the operated side where the afferent termination was known in the dorsal horn of normal animals, the spinal cord segments concerned (tibial N: L_3-S_1, pelvic N: L_6-S_1) were examined by using PAP immunohistochemical technique. The depletive area of SP-like subs-tance in the dorsal horn were significantly clear on the operated side in comparison with the untreated (control) side. The depletive areas of the two groups of animals were different, except for the dorsal gray com- missural nucleus where the depletive areas coincided in the two groups. Very interestingly, these results were similar to the labelling areas re-vealed by HRP transganglionic tracing technique in which HRP was in-jected into the bladder wall and tibial nerve respectively. Our results confirmed that the visceral and somatic primary afferent neurons have their respective SP-like central pathway and terminal areas. To our knowledge this is the first comprehensive report about the central localizing and qualitative study of the visceral afferent system.