Effects of protopine on blood platelet aggregation. II. Effect on metabolic system of adenosine 3',5'-cyclic monophosphate in platelets.
The mode of action of protopine on rabbit platelet aggregation was investigated in the metabolic system of adenosine 3',5'-cyclic monophosphate (cyclic AMP) in vitro experimental models. The inhibitory activity of protopine on adenosine 5'-diphosphate induced platelet aggregation was increased in the presence of prostaglandin I2 or papaverine in platelets. Protopine elevated content of the basal cyclic AMP accumulation in platelets and enhanced activity of crude adenylate cyclase prepared from platelets, but was ineffective on cyclic AMP phosphodiesterase. It is concluded that protopine has an inhibitory activity on platelet aggregation, activates adenylate cyclase and increases cyclic AMP content in platelets, in addition to other inhibitory actions in the metabolic system of cyclic AMP.
Shiomoto
H
H
Faculty of Pharmaceutical Sciences, Kinki University, Osaka, Japan.
Matsuda
H
H
Kubo
M
M
D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D053119:Benzophenanthridines; D001600:Berberine Alkaloids; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism*; D008297:Male; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D011817:Rabbits
D000470:Alkaloids; D053119:Benzophenanthridines; D001600:Berberine Alkaloids; D010975:Platelet Aggregation Inhibitors; D000242:Cyclic AMP; C009093:protopine