Doutrelant O, Poulain P, Carette B, Beauvillain J C
INSERM U 156, Lille, France.
Cell Tissue Res. 1994 Mar;275(3):543-53. doi: 10.1007/BF00318823.
In slices of guinea-pig brains, 36 neurons located in the mediolateral part of the lateral septum were stained intracellularly with horseradish peroxidase (n = 28) or biocytin (n = 8) after electrophysiological characterization. These neurons belonged to class A neurons (n = 23), which generated pronounced Ca(++)-dependent high-threshold spikes in control medium, or to class C neurons (n = 9), which were recognized by the occurrence of small-amplitude sodic spikes followed by slower larger calcic spikes. The present results demonstrate that, despite the variety of individual cell types, the major morphological population (30/36 cells) was composed of a homogeneous class of large-sized neurons that displayed thick primary dendrites and abundant dendritic appendages. The remaining 6 cells were small-sized, poorly-spiny neurons. Somatic spines were observed on 5 out of the 30 large cells and on one out of the six smaller cells. Labeled axons were mainly oriented to the anterior commissure. The axons of nine cells richly collateralized near the perikaryon. Ultrastructural examination of 3 horseradish peroxidase-injected cells showed indented nuclei, classic organelles and somatic spines. Terminal boutons established symmetric synapses with the injected cells. These results describe the morphological features of electrophysiologically identified neurons and indicate that class A and class C neurons are distributed among morphological populations differing in perikaryal size. This suggests that the different electrical properties of class A and class C neurons reflect recordings from different parts of the neuron rather than from neurons of different types. Furthermore, the present findings demonstrate that, in the guinea-pig, electrical and morphological characteristics of somatospiny neurons are comparable with those of non-somatospiny neurons. Somatospiny neurons have a recognized integrative role in the hippocampo-septo-hypothalamic complex.
在豚鼠脑切片中，对36个位于外侧隔中外侧部分的神经元进行电生理特性鉴定后，用辣根过氧化物酶（n = 28）或生物素（n = 8）进行细胞内染色。这些神经元属于A类神经元（n = 23），在对照培养基中产生明显的钙依赖性高阈值尖峰，或属于C类神经元（n = 9），其特征是出现小幅度的钠尖峰，随后是较慢的大幅度钙尖峰。目前的结果表明，尽管存在多种个体细胞类型，但主要的形态学群体（30/36个细胞）由一类同质的大型神经元组成，这些神经元具有粗大的初级树突和丰富的树突附属物。其余6个细胞是小型、棘突较少的神经元。在30个大型细胞中的5个以及6个较小细胞中的1个上观察到了体细胞棘突。标记的轴突主要朝向胼胝体。9个细胞的轴突在胞体附近有丰富的侧支。对3个注射辣根过氧化物酶的细胞进行超微结构检查，显示核凹陷、典型细胞器和体细胞棘突。终末小体与注射细胞形成对称突触。这些结果描述了电生理鉴定神经元的形态学特征，并表明A类和C类神经元分布在胞体大小不同的形态学群体中。这表明A类和C类神经元的不同电特性反映的是来自神经元不同部位的记录，而不是不同类型神经元的记录。此外，目前的研究结果表明在豚鼠中，有体棘神经元的电特性和形态学特征与无体棘神经元相当。有体棘神经元在海马 - 隔 - 下丘脑复合体中具有公认的整合作用。
