巨细胞网状核5-HT能纤维对小脑浦肯野细胞自发电活动的影响

EFFECTS OF GIGANTOCELLULARIS RETICULARIS NUCLEUS STIMULATION ON SPONTANEOUS ACTIVITIES OF PURKINJE CELLS IN THE CEREBELLAR CORTEX OF RATS

用电生理学方法、观察了小脑皮层第Ⅵ—Ⅶ小叶蚓部的浦肯野细胞（Purkinje cell,PC）对巨细胞网状核（Gigantocellularis reticularis nucleus,GI）刺激的反应特性,并观察了颈静脉注射5-羟色胺（5-HT）受体阻断剂二甲麦新碱（Methysergide）后GI刺激的效应。 结果表明:（1）刺激GI对小脑皮层Ⅵ—Ⅶ小叶PC自发放电的影响有抑制（41％）、兴奋（27％）及无明显作用（32％）三种形式,其中以抑制性作用为主。（2）GI刺激引起的PC反应在小脑皮层上呈区域性差异,表现为由VIA（64.3％）、VTB（65.3％）、VIC（71.4％）至Ⅶ小叶（74.2％）PC反应比率逐渐升高。（3）颈静脉注射二甲麦角新碱后,由GI刺激引起的PC自发放电的抑制性效应可逐渐被消除,而兴奋性效应则不被减弱。 结果提示:GI—小脑之间存在着5-HT能纤维投射,这些5-HT能纤维可能以“非突触释放”的形式调节着PC的机能活动。PC对GI刺激反应的区域性差异,可能与GI—小脑5-HT能纤维投射的解剖学分布特性有关。

Experiments were designed to examine the responses of Purkinje cells (PC) in the different cerebellar lobules and zones to GI gantocellularis Reticularis Nucleus (GI) stimulation. The purpose of the present investigation was to study the possible role of 5-HT which origines from GI in the cerebellum.GI stimulation chiefly depressed the spontaneous activities of PC and inhibitory responses had longer latency and shorter effect duration than excitory responses. But in the different cerebellar loubles,the rates of responses of PC to GI stimulation were different. There were more cells modulated in louble Ⅶ(74. 2%) than in louble VIC(71. 4%), VIB(65. 2%) and VIA(64. 3%). When adminstration Methysergide,the rates of responses of inhibitory PC could be decressed.but there were no effects on excitory cells.