摘要
目前有不少作者认为,针刺镇痛作用,可能是针刺信号与痛觉信号在中枢神经系统内相互作用的结果。张香桐^([1])的工作指出,在丘脑的束旁核和中央外侧核中存在有痛敏神经细胞。这些神经元对伤害性刺激可产生特殊形式的单位放电。这种放电的主要特点是:潜伏期较长,放电频率较高,后放电持续时间较久,而且对于重复刺激没有适应性。电针刺激经穴可以抑制这类痛放电。罗氏^([2])的工作表明:电刺激中央中核亦可抑制束旁核痛敏神经元的痛放电,由于这种抑制过程的潜伏期较长,因此推测,中央中核可能通过复杂的神经回路对束旁核产生抑制作用。
It was widely received that the parafasicular nucleus(Pf)and the central lateral nucleus of the thalamus played an important role in the mechanism of the acupuncture analglsia.Consequently,it was necessary to make a careful histological observation on pf in order to provide some data for the investigation of the acupuncture anesthesia mechanism.Five adult rabbits,each weighing about 2 kg,were selected for this experiment.The animals were infused with 10%formalin,their skulls were mounted on the stereotaxic apparatus according to the Sawyer’s atlas.Brains were removed and made serial sections which were stained alternately with Nissl’s method and the silver impregnation method of Glees.The form and size of the Pf was studied with a microprojector,while the diameters of the Pf neurones were measured by a micrometer under immersion microscope.Results were as follows.The diameters of the whole Pf:from dorsal to ventral,were about 1.6~2.2 mm,from anterior to posterior,were 0.9~1.5 mm,the transverse diameters of Pf were about 0.8~1.1 mm.The volume of Pf was about 0.68~1.26 cubic mm.The total number of the neurones in Pf was about 21,000~39,000 unilaterally.The long diameter of the cell soma in Pf was 21.06±6.22μ,the short diameter of the cell soma was 11.20±3.28μ.The ratio of the long diameter to the short diameter of the cell soma was 1.91±0.84.The area of the cell soma was about 143.28±58.92μ~2.The long diameter of the cell nucleus of Pf was 11.74±1.5μ,the short diameter of the cell nucleus was 8.02±2.01μ.The ratio of the long to short diameter of the cell nucleus was 1.44±0.32.The Pf of the rabbit exhibited primary differenciation.The neurones of Pf could be subdivided into three groups:(1)The first group was formed by large and deeply stained cells which were triangular or pyramidal in shape,and distributed mainly in the lateral inferior portion of the Pf.(2)The neurones of the second group were fusiform in shape,concentrated mainly in the medial portion of the Pf.(3)The neurones of the third group were smaller than those of the first group and stained more lightly,they were shortly ellipsoidal in shape and distributd chiefly in the lateral superior portion of the Pf.Statistical analysis showed that there were some differences among the cells in different portions of the Pf.The authors suggested that the large and deeply stained neurones in Pf were quite similar to those of the central lateral nucleus and might belong to pain sensitive neurones.
作者
徐公美
陈惟昌
Xu Gongmei;Chen Weichang(Department of Anatomy,Neimonggu Medical College,Huhehaute)
出处
《解剖学报》
CAS
1980年第1期33-39,116,共8页
Acta Anatomica Sinica
