Protein kinase C translocation in human blood platelets.
Protein kinase C (PKC) activity and translocation in response to the phorbol ester, phorbol 12-myristate, 13-acetate (PMA), serotonin (5-HT) and thrombin was assessed in human platelets. Stimulation with PMA and 5-HT for 10 minutes or thrombin for 1 minute elicited platelet PKC translocation from cytosol to membrane. The catecholamines, norepinephrine or epinephrine at 10 microM concentrations did not induce redistribution of platelet PKC. Serotonin (0.5-100 microM) and the specific 5-HT2 receptor agonist, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) (10-100 microM) but not the 5-HT1A or 5-HT1B agonists, (+/-) 8-hydroxy-dipropylamino-tetralin (8-OH-DPAT) or 5-methoxy-3-3-(1,2,3,6-tetrahydro-4-pyridin) 1H-indole succinate (RU 24969) induced dose-dependent PKC translocations. Serotonin-evoked PKC translocation was blocked by selective 5-HT2 receptor antagonists, ketanserin and spiroperidol. These results suggest that, in human platelets, PMA, thrombin and 5-HT can elicit PKC translocation from cytosol to membrane. Serotonin-induced PKC translocation in platelets is mediated via 5-HT2 receptors.
Wang
H Y
HY
Department of Psychiatry, Medical College of Pennsylvania, Philadelphia 19129.
Friedman
E
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D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology*; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D006801:Humans; D066298:In Vitro Techniques; D007650:Ketanserin / Q000494:pharmacology; D007700:Kinetics; D011493:Protein Kinase C / Q000097:blood*; D012701:Serotonin / Q000494:pharmacology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D013917:Thrombin / Q000494:pharmacology*
D012701:Serotonin; D007650:Ketanserin; D011493:Protein Kinase C; D013917:Thrombin; D013755:Tetradecanoylphorbol Acetate