Bucher Dirk, Johnson Christian D, Marder Eve
Volen Center and Biology Department, Brandeis University, Waltham, Massachusetts 02454-9110, USA.
J Comp Neurol. 2007 Mar 10;501(2):185-205. doi: 10.1002/cne.21169.
The stomatogastric nervous system (STNS) has long been used as a model system for the study of central pattern generation, neuromodulation, and network dynamics. Anatomical studies of the crustacean stomatogastric ganglion (STG) in different species have mostly been restricted to subsets of neurons and/or general structural features. For the first time, we describe the morphology of all STG neurons belonging to the two circuits that produce the well-described pyloric and gastric rhythms in the lobster, Homarus americanus. Somata sit on the dorsal and lateral surface of the STG and send a single primary neurite into the core of the neuropil, which is mostly made up of larger lower order branches. The perimeter of the neuropil consists mostly of finer higher order branches. Immunohistochemical labeling for synaptic proteins is associated with the small diameter branches. Somata positions are not constant but show preferred locations across individuals. The number of copies is constant for all neuron types except the PY and GM neurons (PY neuron number ranges from 3 to 7, and GM neuron number ranges from 6 to 9). Branch structure is largely nondichotomous, and branches can deviate substantially from cylindrical shape. Diameter changes at branch points can be as large as 20-fold. Clearly, the morphology of a specific neuron type can be quite variable from animal to animal.
口胃神经系统（STNS）长期以来一直被用作研究中枢模式生成、神经调节和网络动力学的模型系统。对不同物种的甲壳类口胃神经节（STG）的解剖学研究大多局限于神经元子集和/或一般结构特征。我们首次描述了属于龙虾美洲螯龙虾中产生描述详尽的幽门和胃节律的两个回路的所有STG神经元的形态。胞体位于STG的背侧和外侧表面，并向神经纤维网的核心发出一条单一的初级神经突，神经纤维网主要由较大的低阶分支组成。神经纤维网的周边主要由较细的高阶分支组成。突触蛋白的免疫组织化学标记与小直径分支相关。胞体位置并非恒定不变，而是在个体间呈现出偏好位置。除了PY和GM神经元外，所有神经元类型的拷贝数都是恒定的（PY神经元数量范围为3至7个，GM神经元数量范围为6至9个）。分支结构在很大程度上是非二叉的，并且分支可能会显著偏离圆柱形。分支点处的直径变化可能高达20倍。显然，特定神经元类型的形态在不同动物之间可能会有很大差异。
