内分泌细胞溶酶体的超微结构研究

Ultrastructural Study of Lysosomes in Endocrine Cells

用电镜细胞化学方法研究内分泌细胞溶酶体的结构与功能。研究结果表明,所有内分泌细胞都存在丰富的溶酶体,分泌自噬作用普遍存在于分泌肽类激素的细胞中,自体吞噬活动活跃是分泌类固醇激素细胞的重要特点。溶酶体通过分泌自噬和自体吞噬分别在两类内分泌细胞中参与激素分泌的调节。

Electron microscopic cytochemistry was used to study the structure and function of lysosomes in endocrine cells. The results indicated: (1)that Lysosomes were numerous in all endocrine ceils we observed including five kinds of peptide hormone secreting cells (somatotrophs, mammotrophs, gonadotrophs, thyrotrophs and corticotrophs) and two steroid hormone secreting cells (Leydig ceils and adrenal cortex ceils); (2) that crinophagy, the process in which lysosomes or multivesicular bodies incorporated with secretory granules, exised in all peptide hormone secreting cells we observed. The number of crinophagic vacuoles increased remarkably in hyposecreting gonadotrophs induced by testostrone administration and hyposecreting corticotrophs induced by dexamethasone. This result confirmed that lysosomes played an important role in regulation of peptide hormone secretion by means of crinophagy; (3) that autophagy, the process in which small portions of cytoplasm were sequeted sand degraded by lysosomes, were frequently observed in steroid hormone secreting ceils. The number of autophagic vacuoles increased remarkably in hyposecreting Leydig ceils induced by testostrone and hyposecreting adrenal cortex cells induced by dexamethasone. This finding suggested that the lysosomes in steroid hormone secreting cells also functioned in the regulation of hormone secretion, by the way of autophagy which scavenged a part of steroid-producing apparatus.