[Effect of oxidative stress on myocardial apoptosis, endoplasmic reticulum stress and apoptosis factor in suckling mouse atria myocardium].

Objective: To investigate the relationship between oxidative stress and myocardial apoptosis, endoplasmic reticulum stress, apoptosis-inducing factors in the process of by researching the effect of oxidative stress on myocardial apoptosis, endoplasmic reticulum stress and apoptosis factor--chop, bax, bcl-2 in suckling mouse atria myocardium.
Methods: The primary cultured suckling mouse myocardium were randomly divided into control group and oxidative stress group. Firstly, the suckling mouse atria cardiomyocytes were treated with H ₂ O ₂ at the concentration of 100 m μ mol/L for 2 hours. Then, the index of oxidative stress and anti-oxidative stress superoxide dismutase (SOD), the con-tents of malondialdehyde (MDA) and glutathione (GSH) of this two groups were detected by ELISA. Myocardial apoptosis of the two groups was detected by TUNEL. The expressions of glucose-regulated protein 78 (GRP78), glucose-regulated protein 94 (GRP94), C/EBP homolo-gous protein (chop), Bcl-2 associated X protein (bax), B-cell leukemia 2 protein (bcl-2) mRNA were detected by real time PCR.
Results: Compared with the control group, the viability of SOD and the contents of MDA in oxidative stress group were reduced, the contents of MDA was increased ( P < 0.01). Compared with the control group, the expression of myocardial apoptosis in oxidative stress group was increased( P < 0.01); the expressions of GRP78, GRP94, chop and bax mRNA were increased, while the expression of bcl-2 mRNA was reduced in ox-idative stress group.
Conclusions: Oxidative stress may induce the endoplasmic reticulum stress, activate the expressions of apoptosis factors, and finally increase the myocardial apoptosis of atria cardiomyocytes. This may connected to the incident of atrial fibrillation.