Müller M C, Westheide W
Spezielle Zoologie, Universität Osnabrück, Osnabrück, Germany.
J Morphol. 2000 Aug;245(2):87-98. doi: 10.1002/1097-4687(200008)245:2<87::AID-JMOR1>3.0.CO;2-W.
The nervous systems of juvenile and adult Myzostoma cirriferum Leuckart, 1836, were stained with antisera against 5-HT (5-hydroxytryptamine, serotonin), FMRFamide, and acetylated alpha-tubulin in combination with the indirect fluorescence technique and analyzed by confocal laser scanning microscopy. The central nervous system consists of two small cerebral ganglia, connected by a dorsal commissure, a ventral nerve mass, and a pair of long circumesophageal connectives joining the former to the latter. The two neuropil cords within the ventral nerve mass curve outward and are joined to one another anteriorly and posteriorly. They are connected by 12 commissures, forming a ladder-like system. A single median nerve runs along the midventral axis. In addition to the circumesophageal connectives, 11 peripheral nerves arise from each main cord. The first innervates the anterior body region. The others form five groups of two nerves each, the first and thicker nerve of which is the parapodial nerve, innervating the parapodium and two corresponding cirri. Except for those in the most posterior group, the second nerves innervate the lateral organs and the body periphery. Serotonergic perikarya are arranged in six more or less distinct clusters, the first lying in front of and the other five between the main nerve cords. The distribution pattern of the FMRFamidergic perikarya is less clear and the somata lie between and outside the cords. One pair of dorsolateral longitudinal nerves was visualized by tubulin staining. Peripheral nerves and the commissures, in particular, demonstrate a segmental organization of the nervous system of M. cirriferum. Furthermore, their arrangement indicates that the body consists of six segments, the first of which is identifiable only by the first pair of peripheral nerves, the first two commissures, and the anteriormost ventral ganglion. The nervous system M. cirriferum thus exhibits several structures also found in the basic plan of the polychaete nervous system.
1836年的卷口涡虫（Myzostoma cirriferum Leuckart）幼体和成体的神经系统，用抗5-羟色胺（5-羟基色胺，血清素）、FMRF酰胺和乙酰化α-微管蛋白的抗血清结合间接荧光技术进行染色，并通过共聚焦激光扫描显微镜进行分析。中枢神经系统由两个小的脑神经节组成，通过背侧连合相连，还有一个腹侧神经团以及一对长的围食管连合，将前者与后者连接起来。腹侧神经团内的两条神经纤维索向外弯曲，并在前后相互连接。它们通过12个连合相连，形成一个梯状系统。一条单一的正中神经沿着腹侧中轴线延伸。除了围食管连合外，每条主索还发出11条外周神经。第一条神经支配身体前部区域。其他神经形成五组，每组两条神经，其中第一条且较粗的神经是疣足神经，支配疣足和两条相应的触须。除了最后一组中的神经外，第二条神经支配侧器官和身体周边。5-羟色胺能神经细胞体排列成六个或多或少明显的簇，第一个簇位于主神经索前方，其他五个簇位于主神经索之间。FMRF酰胺能神经细胞体的分布模式不太清晰，其胞体位于神经索之间和外侧。通过微管蛋白染色观察到一对背外侧纵神经。外周神经和连合，特别是显示出卷口涡虫神经系统的节段性组织。此外，它们的排列表明身体由六个节段组成，其中第一个节段仅通过第一对外周神经、前两个连合和最前端的腹侧神经节来识别。因此，卷口涡虫的神经系统展现出多毛纲神经系统基本结构中也存在的几种结构。
