鸡胸腺APUD(样)细胞的超微结构观察

Ultrastructure of the APUD-Like Cells in the Thymus of Chicken

应用透射电镜在鸡胸腺内观察到一类APUD（样）细胞．其主要特征是胞质内含有膜包小分泌颗粒，颗粒的形态、大小、数量、内部结构及电子密度等有差异．有的颗粒为中等电子密度，有的为均质状高电子密度，有的在中等电子密度中含有一高电子密度的致密核芯；在高倍放大下，有的颗粒在界膜与内含物之间有一低电子密度的晕轮，宽10～20nm．根据其超微结构特征，可将这类细胞分为3型：Ⅰ型细胞的分泌颗粒呈圆形，直径150～380nm；Ⅱ型细胞的分泌颗粒呈圆形、椭圆形、杆状或略微不规则形，直径230～650nm；Ⅲ型细胞所含分泌颗粒甚少，可能是Ⅰ或（和）Ⅱ型细胞的幼稚型．

APUD-like cells were found in the thymus of chicken under the transmission electron microscope. The main characteristics of the cells were that their cytoplasm contained numerous small membrane-bound secretory granules, which were different in shape,size number, substructure, and electron density. Some of the secretory granules were of electron-moderate, and some were almost homogeneously electron-dense, while others were of electron-moderate with an election-dense core. Under high magnification, some of them had a halo which was 10~20 nm in width between the boundary membrane and the inclusions. According to the ultrastructural feataures, the cells could be classified into 3 types: the secretory granules of the type 1 cells were round, approximately 150～380 nm in diameter; those of the type 2cells were round, elliptic, rod-like or irregular-shaped, approximately 230～650 nm in diameter; those of the type 3 cells were rare, this kind of cells being probably precursor of the type 1 and/or type 2 cells.