McCarthy S A, Bicknell R
Imperial Cancer Research Fund Laboratories, University of Oxford, John Radcliffe Hospital, United Kingdom.
J Biol Chem. 1993 Nov 5;268(31):23066-71.
The demonstration of type 2 activin receptor expression in human umbilical vein endothelial cells prompted an investigation of the effects of the activin/inhibin family of hormones on vascular endothelial cell growth. Recombinant activin-A inhibited [3H]methylthymidine uptake and growth of a panel of endothelial cell types; recombinant inhibin-A was without effect. Affinity cross-linking studies demonstrated the presence of type 1 and type 2 activin receptors on the surface of bovine aortic endothelial cells, while detailed analysis of type 2 activin receptor expression revealed both type 2 and type 2B activin receptor mRNA in all endothelial cell types analyzed. In addition, capillary endothelial cells were found to express activin-beta A subunit mRNA and protein, the levels of which were increased in response to transforming growth factor (TGF)-beta. Furthermore, activin-A and TGF-beta caused additive inhibition of capillary endothelial cell [3H]methylthymidine uptake. These findings implicate the activins in the regulation of endothelial cell function, and suggest that TGF-beta and activin may interact to inhibit capillary endothelial cell growth.
在人脐静脉内皮细胞中2型激活素受体表达的证实促使人们研究激活素/抑制素家族激素对血管内皮细胞生长的影响。重组激活素-A抑制了一组内皮细胞类型的[3H]甲基胸苷摄取和生长；重组抑制素-A则无作用。亲和交联研究表明牛主动脉内皮细胞表面存在1型和2型激活素受体，而对2型激活素受体表达的详细分析显示，在所有分析的内皮细胞类型中均存在2型和2B型激活素受体mRNA。此外，发现毛细血管内皮细胞表达激活素-βA亚基mRNA和蛋白，其水平在转化生长因子（TGF）-β刺激下升高。此外，激活素-A和TGF-β对毛细血管内皮细胞[3H]甲基胸苷摄取产生相加性抑制作用。这些发现表明激活素参与内皮细胞功能的调节，并提示TGF-β和激活素可能相互作用以抑制毛细血管内皮细胞生长。
