[Effect of a phorbol ester (PMA) and forskolin of the G-/F-actin equilibrium in human platelets].
Phorbolester (PMA) and forskolin (FSK) cause a dramatic reorganization of microfilaments in cultured cells. We have incubated human blood platelets with PMA and FSK and we investigated the G-/F-actin equilibrium by the DNase I inhibition assay. PMA incubation (0.8 microM, 5 min, 37 degrees C) leads to an increase of filamentous actin (14.4 +/- 4.0%) compared to control platelets. The effect is rapid, dose-dependent and specific, since the biologically inactive derivative phorbol 12,13-didecanoate has no effect. FSK incubation (4 microM, 5 min, 37 degrees C) causes a decrease of F-actin (12.8 +/- 9.0%), the effect is rapid and dose-dependent too. Since 8-bromoadenosine 3':5' cyclic monophosphate also decreases F-actin in human blood platelets, the FSK effect seems to be mediated by cyclic AMP due to affecting the adenylate cyclase.
Spangenberg
P
P
Institut für Pathologiche Biochemie, Medizinischen Akademie Erfurt, DDR.
Koteliansky
V E
VE
Lukashev
M E
ME
Till
U
U
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000199:Actins / Q000097:blood*; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology*; D000242:Cyclic AMP / Q000097:blood; D003850:Deoxyribonuclease I; D006801:Humans; D007700:Kinetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D000199:Actins; D005576:Colforsin; D015124:8-Bromo Cyclic Adenosine Monophosphate; D000242:Cyclic AMP; D003850:Deoxyribonuclease I; D013755:Tetradecanoylphorbol Acetate
Der Einfluss von Phorbolester (PMA) und Forskolin auf des G-/F-Actin-Gleichgewicht humaner Thrombozyten.