Calcitonin gene-related peptide affects cardiomyocyte apoptosis of neonatal rats induced by oxidized low-density lipoprotein and hypoxia/reoxygenation / 中国组织工程研究

ABSTRACT

BACKGROUND:Previous studies have shown that calcitonin gene-related peptide can be released from cardiac sensory afferent terminals fol owing coronary artery occlusion in rats, indicating the involvement of calcitonin gene-related peptide during pathological process of acute myocardial ischemia. OBJECTIVE:To investigate the effect of calcitonin gene-related peptide on neonatal rat cardiomyocytes apoptosis induced by oxidized low-density lipoprotein and hypoxia/reoxygenation. METHODS:Twenty wel s of primary cultured neonatal rat myocardial cel s were randomly divided into five groupsnormal control group, oxidized low-density lipoprotein group, oxidized low-density lipoprotein hypoxia/reoxygenation group, calcitonin gene-related peptide group and calcitonin gene-related peptide 8-37 group. The cel s in the last four groups were incubated with oxidized low-density lipoprotein for 24 hours before establishing the myocardial hypoxia/reoxygenation model. At 30 minutes prior to hypoxia/reoxygenation, 10-8 mol/L calcitonin gene-related peptide were added into the culture fluid in calcitonin gene-related peptide group;10-7 mol/L competitive antagonist calcitonin gene-related peptide 8-37 of calcitonin gene-related peptide-1 receptor were added at 30 minutes before calcitonin gene-related peptide administration in calcitonin gene-related peptide 8-37 group. Myocardial apoptotic rate and caspase-3 activity were detected respectively. RESULTS AND CONCLUSION:Calcitonin gene-related peptide could significantly attenuate apoptosis of neonatal rat myocardial cel s through inhibiting the caspase-3 activation induced by oxidized low-density lipoprotein and hypoxia/reoxygenation. And this effect could be partial y reversed by competitive antagonist calcitonin gene-related peptide 8-37 of calcitonin gene-related peptide 1 receptor, indicating that calcitonin gene-related peptide has anti-apoptotic effect in combination with the calcitonin gene-related peptide 1 receptor to inhibit cardiomyocyte apoptosis in neonatal rats induced by oxidized low-density lipoprotein and hypoxia/reoxygenation.