[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. RESULT: The simulated I/R enhanced the expression of CaSR and cardiomyocyte apoptosis. GdCl(3), 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.