6-氧代前列腺素E1与血小板类前列腺素受体的结合

The binding of 6-oxo-prostaglandin E1 to platelet prostanoid receptors.

作者信息

Jaschonek K, Renn W, Weisenberger H

出版信息

Prostaglandins Leukot Med. 1986 Sep;24(1):79-86. doi: 10.1016/0262-1746(86)90210-6.

PMID:3020591

Abstract

6-oxo-PGE1 has been shown to cause a dose dependent stimulation of platelet adenylate cyclase (Km 1.6 X 10(-7)M). Since this compound also displaced specifically bound 9-3H-PGI2 from intact washed platelets (Ki 1.6 X 10(-6)M), the coupling to platelet PGI2 receptors has been suggested to account for the observed platelet cyclase stimulation. However, the Ki/Km-ratio of 6-oxo-PGE1 appears to be high (10.3) as compared to PGI2, ZK 36 374, and PGE1 (1.9, 2.4 and 3.1, resp.). Thus, one might expect that 6-oxo-PGE1 interacts with a heterogeneous population of platelet receptors mediating the same biological response, eg cyclase activation. In this study, we present evidence supporting this concept and report that 6-oxo-PGE1 also displaces specifically bound 3H-PGD2 from its platelet receptor (Ki 1.6 X 10(-5)M).

摘要

已证明6-氧代前列地尔（6-oxo-PGE1）能引起血小板腺苷酸环化酶的剂量依赖性刺激（米氏常数Km为1.6×10⁻⁷M）。由于该化合物还能从完整的洗涤血小板中特异性取代与9-³H-前列环素（PGI2）结合的物质（抑制常数Ki为1.6×10⁻⁶M），因此有人提出与血小板PGI2受体的偶联可解释所观察到的血小板环化酶刺激现象。然而，与PGI2、ZK 36 374和前列地尔（PGE1）相比（分别为1.9、2.4和3.1），6-氧代前列地尔的Ki/Km比值似乎较高（10.3）。因此，人们可能预期6-氧代前列地尔与介导相同生物学反应（如环化酶激活）的血小板受体异质群体相互作用。在本研究中，我们提供了支持这一概念的证据，并报告6-氧代前列地尔还能从其血小板受体中特异性取代与³H-前列二醇（PGD2）结合的物质（Ki为1.6×10⁻⁵M）。