家兔海马的空间有序构筑以及海马—穹窿—乳头丘脑系统的定量研究

RESEARCH ON THE QUANTITATIVE ANALYSIS OF THE HIPPOCAMPUS—FORNIX—MAMILLOTHALAMIC SYSTEMS AND THE SPATIAL SEQUENTIAL STRUCTURE IN THE HIPPOCAMPUS OF THE RABBIT

本文用家兔九只。五只按Sawyer氏法定位,沿APO平面作额面连续切片,另四只剥离大脑皮质,暴露海马,作海马部位的连续切片。交替用尼氏法和Glees法镀银染色,结果如下:1.海马:长度为28~36mm,宽6~8.5mm,厚2.68~3.39mm。海马内锥体细胞总数平均为7.36×10^(6)个,颗粒细胞总数为4.93×10^(6)个,篮细胞总数为2.40×10^(5)个。锥体细胞:颗粒细胞:篮细胞=30:20:1。CA_(1)区锥体细胞总数为4.11×10^(6)个,CA_(3)区锥体细胞总数为2.48×10^(6)个;CA_(1):CA_(3)=1.66:1。从胞体面积及胞核面积的统计学分析看,二者在形态上有一定差异。海马内结构的另一特点是锥体细胞之主干树突与齿状回的颗粒细胞排列紧密有序,类似阵列结构。2.单侧穹窿柱(FN)的神经纤维总数平均为83,700根,单侧乳头丘脑束(MT)的神经纤维总数为58,740根;MT:FN=1:1.42。3.乳头体核组细胞总数为113,500个,丘脑前核组为165,600个;乳头体核组:丘脑前核组=1:1.46。结合以上结果,对海马结构特点的机能意义进行了讨论。

Nine adult rabbits,perfused with 10%formalin,were used in this experiment.Five of them were mounted on the stereotaxic apparatus according to the Sawyer's atlas.Brains were removed and made serial sections including thalamus and hippocampus.The neocortices of the other four rabbits were removed and the hippocampal formations were exposed.Serial sections of the hippocampus were made and stained alternately with Nissl's method and the silver impregnation method of Glees.The results could be summarized as follows.1.The hippocampus measured 28.00-36.00 mm in length,6.00-8.50 mm in breadth and 2.68-3.39 mm in thickness.The total numbers of the pyramidal cells(CA_(1)-CA_(4)),the granular cells in the dentate gyrus and the basket cells were 7.36×10^(6),4.93×10^(6),2.40×10^(5)respectively.The ratio of the total numbers among the pyramidal,granular and the basket cells was 30:20:1 approximately.The total number of the CA_(1)pyramidal neurones was 4.11×10^(6),and that of the CA_(3)was 2.48×10^(6).The ratio of the numbers of the CA_(1)and CA_(3)neurones was 1.66:1.2.The arrangements of the granular cells in the dentate gyrus and the apical dentrites of the CA_(1)neurones were rather regular and possessed a typical array-like structure.3.The total numbers of the fibers in the column fornix(FN)and the mamillothalamic tract(MT)were 83700 and 58740 respectively.MT:FN=1:1.42.The total number of the neurones in the mamillary nucleus was 113500,and that of the anterior thalamic nucleus was 165600.The ratio of the neurones between these two nuclei was 1:1.46.According to the results mentioned above,the functional significance of the characteristic structure of the hippocampus was also discussed.