Submaximal inhibition of protein kinase C restores ADP-induced dense granule secretion in platelets in the presence of Ca2+.

ABSTRACT: Protein kinase C (PKC) is a family of serine/threonine kinases that play isoform-specific inhibitory and stimulatory roles in platelet activation. We show here that the pan-PKC inhibitor Ro31-8220 can be used to dissect these events following platelet activation by ADP. Submaximal concentrations of Ro31-8220 potentiated aggregation and dense granule secretion to ADP in plasma anticoagulated with citrate, in D-Phe-Pro-Arg-chloromethyl ketone-anticoagulated plasma, which has physiological levels of Ca(2+), and in washed platelets. Potentiation was retained on inhibition of cyclooxygenase and was associated with an increase in intracellular Ca(2+). Potentiation of aggregation and secretion was abolished by a maximally effective concentration of Ro31-8220, consistent with a critical role of PK

SUBMITTER: Unsworth AJ 

PROVIDER: S-EPMC3122168 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature