Clozel M, Fischli W
F. Hoffmann-La Roche and Co., AG, Basel, Switzerland.
J Cardiovasc Pharmacol. 1989;13 Suppl 5:S229-31. doi: 10.1097/00005344-198900135-00068.
Endothelin-1 (ET-1) has been identified in the conditioned medium of porcine endothelial cells. Human endothelin (ET-1) cloned from a placenta cDNA library is similar to porcine, but it is not known whether endothelin itself is secreted by human endothelial cells. To answer this question, a conditioned medium taken every 48 h from confluent cultures of umbilical vein endothelial cells was analyzed by HPLC and all fractions were tested for their ability to inhibit [125I]ET-1 binding on human placenta membranes. Only one fraction did inhibit [125I]ET-1 binding. When the conditioned medium was spiked with ET-1, the same single fraction inhibited [125I]ET-1 binding showing that ET-1, itself, is present in the conditioned medium of human endothelial cells. ET-1 accumulates with time, reaching a plateau at 48 h. ET-1 secretion is not increased by a 24-h incubation of endothelial cells with phorbol myristate acetate, interleukin-1, tumor necrosis factor, thrombin or neuropeptide Y.
内皮素-1（ET-1）已在猪内皮细胞的条件培养基中被鉴定出来。从胎盘cDNA文库克隆的人内皮素（ET-1）与猪的相似，但尚不清楚内皮素本身是否由人内皮细胞分泌。为了回答这个问题，通过高效液相色谱法（HPLC）分析了从脐静脉内皮细胞汇合培养物中每48小时获取一次的条件培养基，并检测了所有级分抑制[125I]ET-1与人胎盘膜结合的能力。只有一个级分确实抑制了[125I]ET-1的结合。当条件培养基中加入ET-1时，相同的单一级分抑制了[125I]ET-1的结合，表明ET-1本身存在于人内皮细胞的条件培养基中。ET-1随时间积累，在48小时达到平台期。用佛波醇肉豆蔻酸酯乙酸盐、白细胞介素-1、肿瘤坏死因子、凝血酶或神经肽Y对内皮细胞进行24小时孵育，并不会增加ET-1的分泌。
