Abrahams S J, Holtzman E
J Cell Biol. 1973 Feb;56(2):540-58. doi: 10.1083/jcb.56.2.540.
Insulin was used to deplete the adrenalin stores of rat adrenal medulla cells. Release of secretion was observed to occur by exocytosis. In addition, during the stages of massive release of secretory granules, the insulin-treated preparations showed greatly enhanced endocytic uptake of horseradish peroxidase. The tracer was taken up within vesicles, tubules, multivesicular bodies, and dense bodies. From acid phosphatase studies and from previous work it appears that many of the structures in which peroxidase accumulates are lysosomes or are destined to fuse with lysosomes. Subsequent to the period of intense exocytosis and endocytosis, there is a transient accumulation of lipid droplets in the adrenalin cells. The cells then regranulate, with new granules forming near the Golgi region. These results suggest that under the conditions used, much of the membrane that initially surrounds secretory granules is degraded after release of the granules.
胰岛素被用于耗尽大鼠肾上腺髓质细胞的肾上腺素储备。观察到分泌通过胞吐作用释放。此外，在分泌颗粒大量释放阶段，经胰岛素处理的制剂显示辣根过氧化物酶的内吞摄取大大增强。示踪剂被摄取到小泡、小管、多泡体和致密体中。从酸性磷酸酶研究和先前的工作来看，过氧化物酶积累的许多结构似乎是溶酶体或注定要与溶酶体融合。在强烈的胞吐作用和内吞作用阶段之后，肾上腺素细胞中会短暂积累脂滴。然后细胞重新形成颗粒，新的颗粒在高尔基体区域附近形成。这些结果表明，在所使用的条件下，最初围绕分泌颗粒的许多膜在颗粒释放后会被降解。
