| 摘要: |
| 采用显微及亚显微观察方法, 研究了可口革囊星虫肾管的形态结构特征。结果表明, 可口革囊星虫肾管由排泄囊及排泄管组成, 外表面具瓶形突起。肾管壁从内到外由上皮层、肌层、细胞外基质及外膜构成。上皮层的单层柱状细胞在肾管腔面成束排列、单层立方细胞围绕瓶形突起内腔排列, 两种上皮细胞的游离面均着生微绒毛及纤毛, 细胞质中细胞器发达, 并含有不同大小、形态及电子致密度的颗粒; 柱状细胞基底面质膜内陷形成基底迷路。肌层由环肌及纵肌组成。细胞外基质主要由胶原原纤维构成, 内含颗粒细胞。外膜由足细胞及多纤毛细胞构成。肾管通过肾孔通体外、肾口通体腔。肾管的结构特征与其对体腔液的过滤排泄功能相适应, 繁殖季节肾管兼具生殖管的作用。 |
| 关键词: 可口革囊星虫 肾管 显微结构 超微结构 功能 |
| DOI：10.11693/hyhz201304024024 |
| 分类号: |
| 基金项目: |
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| MORPHOLOGICAL FEATURES OF NEPHRIDIUM IN THE SIPUNCULAN PHASCOLOSOMA ESCULENTA UNDER LIGHT AND ELECTRON MICROSCOPY |
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MU Dan-Li1, LONG Ling-Li1, LU Ming-Ming1, ZHU Jun-Quan1, DING Li-Fa2
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1.Key Laboratory of Applied Marine Biotechnology by the Ministry of Education, Ningbo University;2.Wenling Fisheries Technology Extension Station
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| Abstract: |
| Morphological characteristics of nephridium in sipunculan Phascolosoma esculenta were observed by light and electron microscopy. The nephridium of P. esculenta consists of excretory sac and excretory tube, with the flask-shaped infoldings on the external surface. The nephridial wall is constructed of epithelium, muscle layer, extracellular matrix and adventitia. The epithelium is differentiated into simple columnar cells arranged into bunches facing the lumen of the nephridium and simple cubical cells that line the lumens of the flask-shaped infoldings. The cytoplasm of the epithelial cells contains well-developed organelles and numerous granules of different sizes, shapes, and electron-densities, while the free surface bears microvilli and cilia. The basal labyrinth is formed by invagination of the basal membrane of columnar cells. Muscle layer is comprised of circular and longitudinal muscles. Granulocytes are present in the extracellular matrix, which is made up of collagen fibrils. Adventitia is composed of the system of podocytes and multiciliary cells. The nephridium opens to the outside via a nephropore and into the coelomic cavity via a nephrostome. These structural features of the nephridium acting as a gonoduct during the spawning period are coincident with its functions of filtration and excretion. |
| Key words: Phascolosoma esculenta nephridium microstructure ultrastructure function |
