摘要
目的:研究腺苷对血小板中肌醇磷脂和蛋白质磷酸化的影响.方法:在Mg^(2+)和/或Ca^(2+)存在下,用猪血小板膜与[γ-^(32)P]ATP在30℃下保温3 min,测定^(32)P掺入磷脂或蛋白质.结果:5′-氯-5′-脱氧腺苷减少磷脂酰肌醇-4-磷酸和磷脂酰肌醇-4,5-二磷酸的生成[IC_(50)分别为71和75(95％可信限分别为60-85和62-90)μmol·L^(-1)],抑制与ATP呈竞争性,并抑制pleckstrin(C激酶主要底物)和肌球蛋白轻链的磷酸化[IC_(50)分别为75和82(95％可信限分别为62·90和66-102)μmol·L^(-1)].结论:腺苷影响血小板中肌醇磷脂信使通路,这有助于阐明腺苷对血小板活化的抑制作用.
AIM: To study the effects of adenosine on the phosphorylation of phosphoinositides and proteins in platelets. METHODS: In the presence of Mg2+ and/or Ca2+ , swine throm-bocytic membranes were incubated with [r-32P]ATP at 30 C for 3 min and the incorporations of 32P into phospholipids or proteins were measured. RESULTS:5 '-Chloro-5' -deoxyadenosine decreased the formation of phosphatidylinositol 4-phosphate and phosphatidylinositol 4, 5-bisphosphate [IC50 71 and 75 (95 % confidence limits 60 -85 and 62 - 90)umol·L-1, respectively], behaving as a competitive inhibitor to ATP, and inhibited the phosphorylation of pleckstrin (the major protein kinase C substrate) and myosin light chain [IC5075 and 82 (95 % confidence limits 62 -90 and 66 - 102)umol.L-1, respectively ]. CONCLUSION: Adenosine affects the phosphoinositide signaling pathway in platelets, which helps to clarify the inhibition of adenosine on platelet activation.
出处
《中国药理学报》
CSCD
1995年第3期247-250,共4页
Acta Pharmacologica Sinica
基金
Project supported by the National Natural Science Foundation of China, №3880443.
关键词
腺苷
血小板
磷肌醇类
蛋白激酶C
磷酸化
adenosine
blood platelets
phosphatidylinositols
protein kinase C
phosphorylation
