Banerjee D K, Ornberg R L, Youdim M B, Heldman E, Pollard H B
Proc Natl Acad Sci U S A. 1985 Jul;82(14):4702-6. doi: 10.1073/pnas.82.14.4702.
The endocrine barrier between chromaffin cells and the blood stream in the adrenal medulla is made of capillary endothelial cells. We have now succeeded in isolating endothelial cells from adrenal medullary tissue, which are probably derived from this barrier. These cells grow on plastic surfaces in the absence of special growth factors or collagen overlays and differentiate into organized structures quite similar to true capillaries. The cells contain factor VIII:R, a marker for endothelial cells, and form intercellular junctions characteristic of capillary endothelial cells. They also synthesize and secrete basal lamina structures and engage in transcytosis, a characteristic ultrastructural and functional combination of exocytosis and endocytosis across the thin endothelial cell processes. These endothelial cells can take up and deaminate catecholamines by A-type monoamine oxidase, an enzyme functionally distinct from the B-type monoamine oxidase found in chromaffin cells. These data indicate that the chromaffin cell and its endothelial cell neighbor may constitute the functional unit of catecholamine metabolism in the adrenal medulla.
肾上腺髓质中嗜铬细胞与血流之间的内分泌屏障由毛细血管内皮细胞构成。我们现已成功从肾上腺髓质组织中分离出内皮细胞，这些细胞可能源自该屏障。这些细胞在没有特殊生长因子或胶原覆盖物的情况下，能在塑料表面生长，并分化成与真正毛细血管非常相似的有组织的结构。这些细胞含有内皮细胞标志物因子VIII:R，并形成毛细血管内皮细胞特有的细胞间连接。它们还合成并分泌基膜结构，参与转胞吞作用，这是一种跨内皮细胞薄突起的胞吐作用和胞吞作用的典型超微结构与功能组合。这些内皮细胞可通过A型单胺氧化酶摄取并脱氨基儿茶酚胺，该酶在功能上与嗜铬细胞中发现的B型单胺氧化酶不同。这些数据表明，嗜铬细胞及其相邻的内皮细胞可能构成肾上腺髓质中儿茶酚胺代谢的功能单位。
