Chia Fu-Shiang, Koss Ron
Department of Zoology, University of Alberta, Edmonton, Alberta, Canada T6G 2E9.
J Morphol. 1979 Jun;160(3):275-297. doi: 10.1002/jmor.1051600303.
The nervous system of the planula larva of Anthopleura elegantissima consists of an apical organ, one type of endodermal receptor cell, two types of ectodermal receptor cells, central neurons and nerve plexus. Both interneural and neuromuscular synapses are found in the nerve plexus. The apical organ is a collection of about 100 long, columnar cells each bearing a long cilium and a collar of about 10 microvilli. The cilia of the apical organ are twisted together to form an apical tuft. The ciliary rootlets of the apical organ cells are extremely long, reaching to the basal processes of the cells adjacent to the mesoglea. All three types of sensory cells are tall and slender in profile and are identified by the presence of one or more of the following features: microtubules, small vesicles, membrane-bound granules and synapses. The interneurons are bipolar cells with somas restricted to the aboral end, adjacent to the apical organ. All synapses observed are polarized or asymmetrical. A diagram including all the elements of the nervous system is presented and the possible functions of the nervous system are discussed in relation to larval behavior.
华丽海葵浮浪幼虫的神经系统由一个顶器、一种内胚层受体细胞、两种外胚层受体细胞、中枢神经元和神经丛组成。神经丛中存在神经间突触和神经肌肉突触。顶器是由大约100个长柱状细胞聚集而成，每个细胞都有一根长纤毛和一个由大约10根微绒毛组成的环。顶器的纤毛扭在一起形成一个顶毛束。顶器细胞的纤毛小根非常长，延伸到与中胶层相邻的细胞的基部突起处。所有三种类型的感觉细胞在外形上都很高且细长，并通过以下一种或多种特征来识别：微管、小泡、膜结合颗粒和突触。中间神经元是双极细胞，其胞体局限于反口端，与顶器相邻。观察到的所有突触都是极化的或不对称的。本文给出了一个包含神经系统所有元素的示意图，并结合幼虫行为讨论了神经系统可能的功能。
