Amiloride analogs stimulate protein phosphorylation and serotonin release in human platelets.
We examined the effects of newly exploited amiloride analogs on protein phosphorylation and serotonin secretion in human platelets. 5-(N-methyl-N-isobutyl) amiloride (IBA) and, to a lesser extent, 5-(N-methyl-N-isopropyl) amiloride (IPA), highly specific inhibitors of Na+/H+-pump, induced the phosphorylation of 47K-dalton protein and myosin light chain (20K). The phosphorylation was inhibited by apyrase. On the other hand, 3', 4'-dichlorobenzamil (DCB) and 2', 4'-dimethylbenzamil (DMB), highly specific inhibitors of Na+/Ca2+-pump, and to a lesser extent amiloride analogs induced serotonin secretion. Apparently there was dissociation between the phosphorylation and the serotonin release induced by the analogs.
Yoshida
K
K
Department of Legal Medicine, Osaka University, Medical School, Japan.
Cragoe
E J
EJ
D000584:Amiloride / Q000031:analogs & derivatives* / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D001798:Blood Proteins / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D010766:Phosphorylation; D012701:Serotonin / Q000097:blood*
D001798:Blood Proteins; D012701:Serotonin; D000584:Amiloride