Phospholamban and Troponin I Are Substrates for Protein Kinase C In Vitro but Not in Intact Beating Guinea Pig
نویسنده
چکیده
The incorporation of [32Plinorganic phosphate into membranous, myofibrillar, and cytosolic proteins was studied in Langendorff-perfused guinea pig hearts treated with phorbol 12myristate 13-acetate (PMA) or 1,2-dioctanoylglycerol (D8G), which are potent activators of protein kinase C. Control hearts were perfused with an inactive phorbol ester (4c-phorbol 12,13-didecanoate), which does not cause activation of protein kinase C. To ensure the blockade of different receptor systems, the perfusions were carried out in the presence of prazosin, propranolol, and atropine. Perfusion of hearts with either PMA (4 AM) or D8G (200 ,uM) was associated with a negative effect on left ventricular inotropy and relaxation. Examination of the
منابع مشابه
Phospholamban and troponin I are substrates for protein kinase C in vitro but not in intact beating guinea pig hearts.
The incorporation of [32P]inorganic phosphate into membranous, myofibrillar, and cytosolic proteins was studied in Langendorff-perfused guinea pig hearts treated with phorbol 12-myristate 13-acetate (PMA) or 1,2-dioctanoylglycerol (D8G), which are potent activators of protein kinase C. Control hearts were perfused with an inactive phorbol ester (4 alpha-phorbol 12,13-didecanoate), which does no...
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The influence of selective (milrinone: 10, 50, 100 microM) and nonselective phosphodiesterase (isobutylmethylxanthine: 0.1, 10, 100 microM) inhibitors and beta-adrenergic stimulation (isoproterenol: 0.01, 0.1 microM) on phospholamban and myofibrillar protein phosphorylation was studied in guinea pig hearts perfused with [32P]orthophosphate. Changes in protein phosphorylation were compared to al...
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