Regulation of platelet cytosolic free calcium by cyclic nucleotides and protein kinase C
- 2 September 1985
- journal article
- Published by Wiley in FEBS Letters
- Vol. 188 (2) , 383-388
- https://doi.org/10.1016/0014-5793(85)80407-5
Abstract
PAF elicits a rapid, concentration-dependent elevation of platelet cytosolic free calcium ([Caf]), measured by quin2. Elevation of [Caf] is transient, and the rate of reversal increases with agonist concentration. Adenylate cyclase stimulants (PGI2, PGD2) and 8-bromo cAMP; a guanylate cyclase stimulant (sodium nitroprusside) and 8-bromo cGMP; and a protein kinase C stimulant (phorbol myristate acetate) block the elevation of [Caf] induced by PAF, and accelerate its reversal. These results suggest that cAMP, cGMP and 1,2-diacylglycerol (DAG) could act as second messengers to regulate [Caf] in platelets. As PAF is known to stimulate platelet phosphoinositide hydrolysis (ergo DAG formation) but fails to elevate platelet cAMP or cGMP, it is proposed that DAG, via activation of protein kinase C, may act as an endogenous modulator of platelet [Caf]: an action that contributes to the role of DAG as a bi-directional regulator of platelet reactivity.Keywords
This publication has 20 references indexed in Scilit:
- Tumor promoter phorbol 12-myristate, 13-acetate inhibits phosphoinositide hydrolysis and cytosolic Ca2+ rise induced by the activation of muscarinic receptors in PC12 cellsBiochemical and Biophysical Research Communications, 1985
- Tumour‐promoting phorbol esters inhibit agonist‐induced phosphatidate formation and Ca2+ flux in human plateletsFEBS Letters, 1985
- Inositol trisphosphate and diacylglycerol as second messengersBiochemical Journal, 1984
- Thromboxane-induced phosphatidate formation in human platelets. Relationship to receptor occupancy and to changes in cytosolic free calciumBiochemical Journal, 1984
- Relationship between structure of phenothiazine analogues and their activity on platelet calcium fluxesBritish Journal of Pharmacology, 1984
- Trifluoperazine and chlorpromazine block secretion from human platelets evoked at basal cytoplasmic free calcium by activators of C‐kinaseFEBS Letters, 1983
- The cytoplasmic concentration of free calcium in platelets is controlled by stimulators of cyclic AMP production (PGD2, PGE1, forskolin)Biochemical and Biophysical Research Communications, 1983
- Inhibitory action of guanosine 3′,5′-monophosphate on thrombin-induced phosphatidylinositol turnover and protein phosphorylation in human plateletsBiochemical and Biophysical Research Communications, 1981
- Phosphorylation of cardiac sarcoplasmic reticulum by a calcium-activated, phospholipid-dependent protein kinaseBiochemical and Biophysical Research Communications, 1980
- Stimulation of calcium uptake in platelet membrane vesicles by adenosine 3′,5′-cyclic monophosphate and protein kinaseBiochimica et Biophysica Acta (BBA) - Biomembranes, 1977