ABSTRACT
To explore influence of interventional closure on heart rate in patients with atrial septal defect . Methods : A total of 63 patients with atrial septal defect undergoing percutaneous interventional closure in our hospi‐tal were selected. Heart rate was compared before and after surgery ,and correlation among heart rate ,age ,occlude size and preoperative pulmonary artery pressure was analyzed .Results : Compared with before surgery ,there was significant reduction in heart rate [(75.22 ± 8.23) beats／min vs. (64.87 ± 10. 65) beats／min] after percutaneous in‐terventional closure of atrial septal defect , P＝0.001 ;Pearson correlation analysis indicated that postoperative heart rate change was not correlated with age ,occluder size and pulmonary artery systolic pressure (PASP ) ( r＝0.017－0.182 , P＞0.05 all) . Compared with patients without preoperative pulmonary artery hypertension ,there was sig‐nificant rise in postoperative reduction amplitude of heart rate [ (2.28 ± 9.81) beats／min vs. (11. 35 ± 10.73) beats／min] in those with preoperative elevated pulmonary systolic pressure (≥25mmHg) , P＝0.038 .Conclusion : After percutaneous interventional closure ,heart rate significantly decreases in patients with atrial septal defect .Presence of preoperative pulmonary artery hypertension can be regarded as a risk predictor for postoperative heart rate reduction .
ABSTRACT
Objective@#To investigate the protective effect of glucose regulatory protein 78 (GRP78) on cardiomyocytes in atrial fibrillation and its mechanism.@*Methods@#HL-1 cardiomyocyte cell line was cultured from June 2016 to March 2017 at Harbin Medical University Central Laboratory.The cells were randomly divided into 4 groups: control group, pacing group, pacing+ GRP78cDNA group, pacing+ GRP78siRNA group.The following indicators were detected: (1)oxidative stress: flow cytometry was used to detect the content of reactive oxygen species (ROS) in each group; (2)Ca2+ overload and cell electrophysiology: flow cytometry was used to detect Ca2+ content in each group; (3)cell structure reconstruction: cell apoptosis was detected by flow cytometry.@*Results@#The ROS production in the pacing group was significantly higher than that in the control group [(28.8±0.5)% vs.(4.5±0.8)%, F=27.91, P<0.01]. The number of ROS in the GRP78siRNA group was significantly higher than that in the pacing group [(71.1±0.3%) vs.(28.8±0.5)%, F=34.12, P<0.01]. The ROS content of the GRP78cDNA group was lower than that of the pacing group [(26.1±2.7)% vs.(28.8±0.5)%, F=26.60, P<0.01]. Pacing significantly increased Ca2+ concentration in HL-1 cells; GRP concentration in HL-1 cells in the GRP78siRNA group was significantly higher than that in the pacing group [(72.53±2.5)AM vs.(39.23±1.9)AM, F=19.50, P<0.05]. The intracellular Ca2+ concentration in the GRP78cDNA group was significantly lower than that in the pacing group [(31.23±0.57)AM vs.(39.23±1.9)AM, F=28.17, P<0.01]. The survival rate of the GRP78cDNA group was significantly higher than that of the pacing group [(87.9±0.4)% vs.(80.1±0.5)%, F=19, P<0.05].@*Conclusion@#GRP78 protein reduces intracellular calcium overload by reducing ROS production in myocardial cells during atrial fibrillation.It can alleviate the oxidative stress of cardiomyocytes and improve the survival rate of cardiomyocytes, and has protective effect on cardiomyocytes.
ABSTRACT
Objective To investigate the protective effect of glucose regulatory protein 78 ( GRP78) on cardiomyocytes in atrial fibrillation and its mechanism.Methods HL-1 cardiomyocyte cell line was cultured from June 2016 to March 2017 at Harbin Medical University Central Laboratory. The cells were randomly divided into 4 groups:control group, pacing group, pacing + GRP78cDNA group, pacing + GRP78siRNA group. The following indicators were detected:(1)oxidative stress:flow cytometry was used to detect the content of reactive oxygen species (ROS) in each group;(2)Ca2+ overload and cell electrophysiology:flow cytometry was used to detect Ca2+ content in each group; ( 3 ) cell structure reconstruction: cell apoptosis was detected by flow cytometry. Results The ROS production in the pacing group was significantly higher than that in the control group [(28.8 ± 0.5)% vs.(4.5 ± 0.8)%,F=27.91,P＜0.01].The number of ROS in the GRP78siRNA group was significantly higher than that in the pacing group [(71.1 ± 0.3%) vs.(28.8 ± 0.5)%,F=34.12,P＜0.01].The ROS content of the GRP78cDNA group was lower than that of the pacing group [(26.1 ± 2.7)% vs.(28.8 ± 0.5)%,F=26.60,P＜0.01].Pacing significantly increased Ca2+ concentration in HL-1 cells;GRP concentration in HL-1 cells in the GRP78siRNA group was significantly higher than that in the pacing group [(72.53 ± 2.5)AM vs.(39.23 ± 1.9)AM,F=19.50, P＜0.05].The intracellular Ca2+ concentration in the GRP78cDNA group was significantly lower than that in the pacing group [(31.23 ± 0. 57 ) AM vs.(39. 23 ± 1. 9 ) AM, F =28. 17, P ＜0. 01 ]. The survival rate of the GRP78cDNA group was significantly higher than that of the pacing group [(87.9 ± 0.4)% vs.(80.1 ± 0.5)%,F=19,P＜0.05].Conclusion GRP78 protein reduces intracellular calcium overload by reducing ROS production in myocardial cells during atrial fibrillation.It can alleviate the oxidative stress of cardiomyocytes and improve the survival rate of cardiomyocytes,and has protective effect on cardiomyocytes.