Calcineurin regulates ryanodine receptor/Ca(2+)-release channels in rat heart.

摘要: The present study was undertaken to examine the physical and physiological interaction of protein phosphatase 2B, calcineurin, with ryanodine receptor (RyR) in rat cardiac tissue neonatal cardiomyocytes. presence RyR FK506-binding (FKBP)12.6 sarcoplasmic reticulum (SR) identified by Western blot analysis. possible interactions between FKBP12.6 were further studied co-immunoprecipitation using CHAPS-solubilized cardiac-membrane fractions (CSMFs) or SR preparations. Physical calcineurin found CSMF added 100 microM Ca(2+); however, interrupted 20 mM EGTA, 1 rapamycin FK506, suggesting that is Ca(2+)-dependent, mediated FKBP12.6. Ca(2+)-dependent also co-immunoprecipitation. Effects inhibitors tested on neonatal-rat-heart Treatment cardiomyocytes deltamethrin, 10 cyclosporin A (CsA), mciroM FK506 led Ca(2+) oscillations originally quiescent Preincubation which dissociates from RyR, evoked oscillations, probably due leakiness RyR. However, not affected CsA only RyR-associated could regulate channel activities. In spontaneously Ca(2+)-oscillating cardiomyocytes, treatments increased frequency oscillations. ryanodine-treated failed induce These data show evidence associated modulate release heart.