大麻哈幼鱼与成鱼体肾的组织结构及功能特性

Tissue Structure and Functional Characteristics on Body Kidney of Juvenile and Adult Oncorhynchus keta

【目的】探明大麻哈鱼不同生长阶段体肾的组织结构及功能特性,为大麻哈鱼资源的保护与利用提供依据。【方法】采用常规组织学方法,研究大麻哈幼鱼和成鱼体肾的组织结构及功能特性。【结果】大麻哈鱼的肾脏属A型肾脏,幼鱼的体肾由肾单位、拟淋巴组织和血窦组成,成鱼体肾由肾单位、拟淋巴组织和血管组成;肾单位包括肾小体和肾小管,拟淋巴组织主要由淋巴细胞、粒细胞、血细胞和黑色素巨噬细胞等组成;肾小体数量较少,呈无规律分布,多为单个存在,偶见2个相邻聚集,具有海水硬骨鱼类肾小体特征;肾小管由单层上皮细胞构成,分化为颈段、第一近曲小管、第二近曲小管、远端小管和集合管,其中颈段、第一近曲小管、第二近曲小管管腔内具有刷状缘,远端小管、集合管管腔内无刷状缘;幼鱼和成鱼体肾含有黑色素巨噬细胞,其中成鱼体肾的黑色素巨噬细胞数量较多,且聚集成黑色素巨噬细胞中心。【结论】大麻哈鱼体肾的肾实质中,除有肾单位外还有拟淋巴组织,包含血窦、淋巴细胞、粒细胞及黑色素巨噬细胞,其中肾小管有颈段,但未见具有微绒毛的间段结构;成鱼体肾的黑色素巨噬细胞数量较多,不仅具有排泄功能,亦能发挥少量免疫功能。

【Objective】In order to provide the basis for the protection and utilization of Oncorhynchus keta resources,the tissue structure and functional characteristics of body kidney in O.keta at different growth stages are studied.【Method】The conventional histological method is used to study the tissue structure and functional characteristics of body kidney in juvenile and adult O.keta.【Result】The kidney of O.keta belongs to type A kidney,the body kidney of juvenile O.keta is composed of nephron,lymphoid tissue and blood sinus,while the body kidney of adult O.keta is composed of nephron,lymphoid tissue and blood vessel.The nephron include renal corpuscle and renal tubule,and the lymphoid tissue is mainly composed of lymphocyte,granulocyte,blood cells and melano-macrophage;The renal corpuscle is less with irregular distribution,most of them exist individually,two neighboring renal corpuscles are found occasionally,which has the characteristics of renal corpuscle in marine bony fishes.The renal tubule is composed of epithelial cell monolayer,which is differentiated into the neck,the first and second proximal segment,distal segment and collecting segment.Among them,the lumen of the neck,the first and second proximal segment has brush-shaped border,while the lumen of distal segment and collecting segment has no brush-shaped border.The body kidney of juvenile and adult O.keta contains melano-macrophage,among which the number of melano-macrophage in the adult fish kidney is large and they could cluster into the melano-macrophage center.【Conclusion】The renal parenchymal of body kidney in O.keta has not only nephron but also the lymphoid tissue,containing blood sinus,lymphocyte,granulocyte and melano-macrophage,the renal tubule has the neck segment,but there is no intersegmental structure with microvilli.With more melano-macrophage,the body kidney of adult fish not only has the excretion function but also exerts a small amount of immune function.