[Activation of calcium-sensing receptors is associated with apoptosis in cardiomyocytes under simulated ischemia/reperfusion].

Objective:To examine the association of activation of calcium-sensing receptors(CaSR) with apoptosis in cardiomyocytes under simulated ischemia/reperfusion. Methods:Ventricular cardiomyocytes of neonatal rats were incubated in ischemia-mimetic solution for 2 h,then re-incubated in normal culture medium for 24 h to establish a model of simulated ischemia/reperfusion(I/R).Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL assay).The expression of CaSR mRNA was detected by reverse transcriptase polymerase chain reaction(RT-PCR).The expression of Caspase-3 and Bcl-2 was detected by Western blotting. Results:The simulated I/R enhanced the expression of CaSR and cardiomyocyte apoptosis.GdCl3,a specific activator of CaSR,further increased the expression of CaSR and cardiomyocyte apoptosis,along with upregulation of Caspase-3 and downregulation of Bcl-2. Conclusion:CaSR is associated with I/R injury and apoptosis in neonatal rat ventricular cardiomyocytes via suppressing Bcl-2 and promoting Caspase-3 expression.