Platelet-activating factor antagonism in rabbit platelets by the derivative of ochotensimine isolated from corydalis ochotensis

C. H. Lin, Y. C. Wu, S. T. Lu, T. F. Huang, C. M. Teng

研究成果: 雜誌貢獻文章同行評審

摘要

Dihydroochotensimine (DHO) N-oxide, the derivative of ochotensimine which was isolated from corydalis ochotensis, was investigated for its action on washed rabbit platelets. Low concentration (5-50 μg ml-1) of DHO N-oxide inhibited selectively the aggregation of rabbit platelets induced by platelet-activating factor (PAF) in a concentration-dependent manner. High concentration (> 50 μg ml-1) of DHO N-oxide inhibited the aggregation and ATP release caused by collagen and arachidonic acid and also slightly those by ATP. Although thrombin-induced aggregation was not affected by high concentration of DHO N-oxide, the ATP release reaction was markedly suppressed. Prolongation of the incubation time of DHO N-oxide with platelets did not cause further inhibition and the aggregability of the agent-treated platelets could be restored after washing of platelets. The concentration-response curve of PAF-induced platelet aggregation was parallelly shifted to the right by DHO N-oxide (20, 50 and 100 μg ml-1). The pA2 and pA10 values of DHO N-oxide on PAF-induced platelet aggregation were 5.56 and 4.67, respectively, with a slope value of -1.07. High concentration of DHO N-oxide inhibited the formation of thromboxane B2 caused by arachidonic acid, collagen and thrombin. The formation of inositol monophosphate caused by PAF was almost completely inhibited by DHO N-oxide (50 μg ml-1) and those caused by collagen and thrombin were partially inhibited by DHO N-oxide (200 μg ml-1). PAF-induced rise of the intracellular calcium concentration was suppressed by DHO N-oxide. It is concluded that DHO N-oxide may act as a competitive PAF antagonist at low concentration, and inhibit thromboxane formation and phosphoinositides breakdown at high concentration.
原文英語
頁(從 - 到)121-127
頁數7
期刊Asia Pacific Journal of Pharmacology
7
發行號2
出版狀態已發佈 - 1992
對外發佈

ASJC Scopus subject areas

  • 藥理

指紋

深入研究「Platelet-activating factor antagonism in rabbit platelets by the derivative of ochotensimine isolated from corydalis ochotensis」主題。共同形成了獨特的指紋。

引用此