鳗鲡肝脏、脾脏显微与超微结构

经光镜和电镜观察发现：鳗鲡肝脏的肝小叶不规则。肝细胞胞质内富含多种细胞器及包含物。胆小管由２—４个肝细胞围成，相邻肝细胞间有连接复合体封闭胆小管。肝血窦为有孔型、孔处无隔膜，内有巨噬细胞。窦周隙明显，未见贮脂细胞。肝细胞向胆小管腔与窦周隙面伸出许多指状微绒毛。脾脏内白髓中淋巴细胞聚集成群，未见明显脾小结、淋巴鞘。红髓由脾索与脾窦组成，动脉分支末端（壁厚的毛细血管）可开放于红髓，无明显巨噬细胞中心。脾窦及脾小动脉内皮细胞通常为长杆状、沿血管纵向平行排列。脾窦为有孔型，孔处可见薄的隔膜。脾小动脉内皮外为２—５层平滑肌（多数为纵行）。

STRUCTURE OF LIVER AND SPLEEN OF THE EEL (ANGUILLA JAPONICA)

The liver lobule of Eel (Anguilla japonica Temminck & Schlegel) is irregular in form. The hepatocytes are rich in mitochondria, rough and smooth endoplasmic reticulum, ribo-somes, glycogen and lipid droplets. The bile canaliculi consist of two to four adjacent hepatocytes. Tight junctions, intermediate junctions and desmosomes occur between the adjacent hepatocytes. The hepatic sinusoids are fenestrated, containing kupffer cells. No diaphragms are bresent in fenestra. The perisinusoidal space of Disse is clear. On the surface of hepato-cytes, there are many finger microvillia facing the bile canaliculi and the perisinusoidal space of Disse. The trabeculae are seldom seen in spleen. The spleen is made up of two structures: the white pulp and the red pulp. The lymphocytes of white pulp aggregated into groups. The red pulp is made up of splenic cords and splenic sinusoid. The germinal center, periarterial lymphatic sheath are not clear. The terminal parts of splenic artery usually opened into the red pulp. The melanomacrophage centre is not clear. The end othelial lining cell of splenic artery and splenic sinusoid are usually elongated with tapered ends and parallel to the long axis of the blood vessels. The splenic sinusoids are fenestrated and each fenestra is usually closed by a thin single-layered diaphragm. The media under the splenic arterial endothelium contain two to five layers of smooth muscles cells (usually longitudinal muscles).