前列环素对内皮素生物学效应的拮抗作用

The antagonistic effects of prostacyclin(PGI_2)on biological actions of endothelin

为探讨内皮素（ｅｎｄｏｔｈｅｌｉｎ，ＥＴ）与前列环素（ｐｒｏｓｔａｃｙｃｌｉｎ，ＰＧＩ＿２）间相互作用关系及生理意义，本工作在整体动物、离体血管条及培养的血管平滑肌细胞（ｖａｓｃｕｌａｒｓｍｏｏｔｈｍｕｓｃｌｅｃｅｌｌ，ＶＳＭＣ）上发现：ＰＧＩ＿２有效拮抗ＥＴ＿１引起的大鼠升压作用；剂量依赖地逆转ＥＴ＿１对小鼠的致死作用；抑制ＥＴ＿１促培养的大鼠ＶＳＭＣ增殖效应；减少大鼠离体肠系膜上动脉ＥＴ＿１的基础释放及凝血酶刺激的ＥＴ１释放。结果表明：ＰＧＩ＿２能有效拮抗ＥＴ的生物学效应，并提示血管内皮细胞所释放的ＰＧＩ＿２和ＥＴ间存在反馈调节。

In order to investigate the interaction between PGI_2 and endothelin(ET),and its physiological significance,in vivo and in vitro experiments were carried out.Theresults showed that PGI_2 administration to rats effectively inhibited blood pressure elevationinduced by ET_1;PGI_2 reversed the ET _1 lethal effect on mice in a dose-dependent manner;PGI_2 antagonized ET_1-stimulated proliferation of cultured rat’s aortic smooth muscle cells;and PGI_2 reduced basic ET-1 release and thrombin-induced ET_1 release from isolated mesenteric artery. It was indicated that PGI_2 antagonized biological actions of ET_1 effectively,which suggested that a feedback mechanism could exist in vivo between ET and PGI_2 relea-sed from vascular endothelial cells.