Westphal M, Li C H
Int J Pept Protein Res. 1985 Nov;26(5):557-9. doi: 10.1111/j.1399-3011.1985.tb01023.x.
Two human retinoblastoma cell lines (Y79 and McA) were evaluated for the presence of binding sites for human beta-endorphin (beta h-EP). Using tritiated beta h-EP (3H-beta h-EP) and synthetic beta-EP analogues, it was possible to demonstrate binding sites for 3H-beta h-EP with an ED50 of 3.5 nM in Y79 cells and 8 nM in McA cells respectively. The non-opioid segment [beta h-EP-(6-31)] retained about 20% relative potency in Y79 and 40% in McA in displacing the tritiated hormone when compared with beta h-EP. Camel beta-EP had a relative potency of less than 1% and beta h-EP-(1-27) was inactive in both cells in doses as high as 4 microM. Taken together with previous reports on similar binding sites in human neuroblastoma and glioblastoma cell lines, it appears that cell lines of neural origin have binding sites for the COOH-terminal of human beta-EP.
对两个人视网膜母细胞瘤细胞系（Y79和McA）进行了人β-内啡肽（βh-EP）结合位点的评估。使用氚标记的βh-EP（3H-βh-EP）和合成的β-EP类似物，有可能证明Y79细胞中3H-βh-EP的结合位点，其半数有效剂量（ED50）为3.5 nM，McA细胞中为8 nM。与βh-EP相比，非阿片样物质片段[βh-EP-(6-31)]在Y79细胞中取代氚标记激素时保留约20%的相对效力，在McA细胞中为40%。骆驼β-EP的相对效力小于1%，βh-EP-(1-27)在两种细胞中高达4μM的剂量下均无活性。结合先前关于人神经母细胞瘤和胶质母细胞瘤细胞系中类似结合位点的报道，似乎神经源性细胞系具有人β-EP羧基末端的结合位点。
