| 摘要: |
| X器官-窦腺(XO-SG)复合体是甲壳动物重要神经内分泌器官，类似哺乳动物的下丘脑-垂体系统，它能分泌多种神经肽类激素，调控甲壳动物的生殖、发育和蜕皮等重要生理功能(Cooke et al.，1982； Keller，1992)。对XO-SG复合体的研究一直是甲壳动物内分泌学的重点内容。XO由视神经节内一群相互无连接的单轴突分泌肽神经细胞组成，它们的轴突末梢在血窦附近膨大形成窦腺，XO内胞体形成的神经肽类激素经轴突运输到窦腺储存和释放。近20年来，一些学者对10余种甲壳动物眼柄内X器官-窦腺复合体进了形态及超微结构研究，发现X器官神经内分泌细胞胞体的分布位置和结构特征各不相同，区分出2至7种不同类型的神经内分泌末梢，并观察到多种神经内分泌物质释放方式(Fingerman，1992； Dircksen，1992； Castany，1997； Weatherby，1981)。我国对甲壳动物神经内分泌系统的研究刚刚开始(蔡生力，1998)，仅对锯缘青蟹(Scylla serrata)、罗氏沼虹虾(Macrobrachium rosenbergii)和中华绒螯蟹(Eriocheir sinensis)XO-SG复合体进行了显微和超微结构观察(上官步敏等，1994，1995；姚泊，1995；孙金生等，2000)。中国对虾(Penaeus sinensis)是我国重要经济甲壳动物，在育苗过程中往往采用切断或灼烧眼柄的方法来加速亲虾性腺发育和产卵，而对XO-SG复合体却了解甚少，仅进行了组织学观察(康现江等，1998)。为此作者对中国对虾眼柄XO-SG复合体显微和超微结构及其分泌物特征进行了初步研究，为进一步研究对虾神经分泌细胞的离体培养和神经分泌调控机制打下基础。 |
| 关键词: XO-SG复合体 结构 分泌物 |
| DOI： |
| 分类号: |
| 基金项目:中国科学院海洋研究所调查研究报告第4236号。国家重点基础研究资助项目（G1999012007号）。 |
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| PRELIMINARY STUDY ON THE XO-SG COMPLEX AND ITS SECRETION IN THE CHINESE SHRIMP (PENAEUS CHINENSIS) |
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Sun Jinsheng1, Xiang Jianhai2
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1.Tianjin Fishery Institute;2.Institute of Oceanology, Chinese Academy of Sciences
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| Abstract: |
| The authors' light and transimission electron microscopy examination of the X-organ (XO)-sinus gland (SG) complex in adult cultured Chinese shrimp (Penaeus chinensis) revealed that its SG was composed of inner sinus and outer sinus and located on the lateral side of the medulla interna and dorsal medulla terminalia separately. Only one cell type like neurosecretory cells was found in the medulla terminalia. Transimission electron microscopic examination revealed that the SG was mainly composed of enlarged axon terminals abutting on the thin basal lamina of a central hemolymph lacuna acting as a storage release centre for the membrane bound neurosecretory material. Also present in the SG were glial cells with cytoplasmic processes which enwrap the terminals. Four types of neurosecretory terminals were distinguished on the basis of size, morphology and electron density of the neurosecretory granules. Each axon terminal contained only 1 type of granule; the mean granule diameter ranged from 137 nm (type 4) to 236 nm (type 1). Neurosecretory granules exocytosis was not observed in the SG of the Chinese shrimp. To our knowledge, the villus originated from the lamina was not found in the SG of crustaceans dispite of Chinese shrimp, some images showed that villus were related with the releasing of granules from the neurosecretory granules.
Examination of the SG ultrastructure showed the existence of four kinds of neuropeptides that could be separated from the SG extraction by high performance capillary electrophoresis in 50 μm i.d. X 37 cm (33cm effective length) amino-coated capillary, with 0.1 mol/L boracic acid buffer (PH 8.0) as running buffer at 18℃ and 6kv running voltage[(-)-(+)]. |
| Key words: XO-SG complex secretion |
