日本沼虾输精管的结构及其在精荚形成中作用的研究

应用光镜和透射电镜技术研究了日本沼虾输精管的结构及其在精荚形成中的作用。结果表明，日本沼虾输精管从形态结构上可分为近端输精管、卷曲输精管、远端输精管和膨大的远端输精管四部分。各部分的管壁皆由分泌上皮、基膜、肌肉层和结缔组织构成，其中分泌上皮包括高度明显不同的低柱状上皮和高拄状上皮两部分。输精管各部分管腔内含有处于不同形成阶段的精荚。进入近端输精管内的精子被支撑在一种嗜酸性基质中。近端输精管的分泌物主要帮助形成精子团，同时形成精荚壁的极小部分。卷曲和远端输精管分泌形成精荚壁的绝大部分，其分泌物由细胞顶端通过外排作用和顶泌机制分泌产生。膨大的远端输精管具有贮存精荚的作用，其分泌上皮也通过外排作用和顶泌机制产生分泌物包裹在已基本形成的精荚外侧，管壁肌肉层在雌雄交配时将管腔内的精荚切割成适宜长度并排出体外。

STUDIES ON THE ULTRASTRUCTURE AND ROLE OF THE VAS DEFERENS IN SPERMATOPHORE FORMATION OF MACROBRACHIUM NIPPONENSE

The ultrastructure and role of the vas deferens in spermatophore formation of Macrobrachium nipponense were studied by light microscopy and transmission electron microscopy. The vas deferens of Macrobrachium nipponense can be divided morphologically into proximal, convolutal, distal and enlarged distal regions. In cross sections the vas deferens is comprised of secretory epithelia, basal lamila, muscle layer and connective tissue. The secretory epithelia consist of high and low columnar epithelia. The lumen of the vas deferens contains the spermatophore in various stages of development. Sperms entering the proximal vas deferens are supported in an eosinophilic matrix. The secretory products from the proximal vas deferens aid mainly to form a sperm mass and also form a minimum of spermatophoric wall. The convoluted and distal vas deferes secret a maximal part of spermatophoric wall, and their secreory products are released at the apex of the epithelitum by both exocytosis and apocrine mechanisms. The enlarged diatal vas deferens functions in storing the mature spermatophore, and its secretory epithelium secrets products by both exocytosis and apocrine mechanisms to surround the nearly formed spermatophore. Its muscle layer can pinch off individual spermatophores and extrude them from the tract during mating.