Protein kinase C-mediated preconditioning of cardiac myocytes : role of adenosine receptor and KATP channel

摘要: Activation of the adenosine receptor, protein kinase C (PKC), and ATP-sensitive potassium (KATP) channel is known to induce preconditioning. The objective here was determine signaling role PKC, KATP temporal sequence activation these three mediators in preconditioning cardiac myocytes. Chick embryo ventricular myocytes were used as a myocyte model Brief hypoxic or exposure preconditioned myocytes, PKC inhibitors chelerythrine calphostin blocked this effect, suggesting that an effector distal receptor initiating hypoxia- adenosine-induced activator phorbol 12-myristate 13-acetate (PMA), but not inactive 4 alpha-phorbol [2,13-didecanoate 13-acetate, could precondition myocyte; PMA-induced effect by C. Glibenclamide 5-hydroxydecanoate, when present during 5-min PMA 90-min period, However, presence 8-sulfophenyltheophylline failed block preconditioning, whereas able abolish added period. data provide direct evidence channel, down-stream from PKC-mediated Both are required exert actual protective sustained hypoxia.