Kucera GL, Rittenhouse SE. Inhibition of GDP beta S of agonist-activated phospholipase C in human platelets requires cell permeabilization.
Biochem Biophys Res Commun 1988;
153:417-21. [PMID:
3377792 DOI:
10.1016/s0006-291x(88)81240-3]
[Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The inhibition by guanosine 5'-[beta-thio]diphosphate (GDP beta S) of phospholipase C was compared in intact and saponin-permeabilized human platelets in order to assess whether effects of GDP beta S on phospholipase C activation unrelated to guanine nucleotide binding function were occurring. GDP beta S exhibited no effect on phospholipase C activity, monitored by phosphatidic acid formation, in intact platelets that were unstimulated or stimulated with 0.5 U/ml thrombin or 20 nM ONO-11113 (a stable thromboxane A2 analogue). However, GDP beta S did cause a marked decrease in the activity of phospholipase C in saponin-permeabilized platelets. Thus GDP beta S is a viable tool for studying the role of G-proteins in transducing receptor-mediated activation of phospholipase C in platelets.
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