Effects of carvedilol on the expression of glucose regulation protein 78 and homologous protein and apoptosis of myocardial cells in hypothermic stress-induced hypertensive rats
10.3969/j.issn.1009-0754.2018.01.011
- VernacularTitle:卡维地洛对低温应激高血压大鼠心肌内质网GRP78和CHOP的表达及心肌细胞凋亡的影响
- Author:
Mengqi LI
1
;
Jun LU
;
Jihong GAN
Author Information
1. 新疆军区总医院心内科
- Keywords:
Hypertension;
Glucose regulation protein 78;
C/EBP homologous protein;
Myocardial cell;
Apoptosis;
Carvedilol
- From:
Journal of Navy Medicine
2018;39(1):29-32
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect of beta-blocker carvedilol on myocardial endoplasmic reticulum by comparing changes in the expressions of glucose regulation protein 78(GRP78)and C/EBP homologous protein(CHOP)and apoptosis of myocar-dial cells in hypothermic stress-induced hypertensive rats.Methods Thirty male SD rats were randomly divided into the sham group, the CIH group and the carvedilol group,each consisting of 10 animals.The rats in the CIH and carvedilol groups were kept in an envi-ronment at a temperature of(4 ±1)℃and relative humidity of 70% for 4 hours every day for the development of hypothermic stress-in-duced hypertension model.The animals in the carvedilol group received medication of carvedilol by gavage a week before surgery.Blood pressure values of each group were determined by carotid artery intubation 6 weeks after experiment started.The expression levels of GRP78 and CHOP proteins were detected by immunohistochemical method,and apoptosis of myocardial cells was detected by TUNNEL method.Results (1)The mean arterial pressure(MAP)of the animals in the carvedilol group [(118.80 ±3.40)mmHg] was signifi-cantly lower than that of the animals in the CIH group(165.20 ±4.40 mmHg),but was higher than that of the animals in the sham group(107.2 ±0.3mmHg).Statistical significance could be seen, when comparisons were made between them(P<0.05).MAP level of the CIH group was higher than that of the sham group,also with statistical significance(P<0.05).(2)The average optical density(AOD)in the expression of GRP78 protein for the CIH group(0.34 ±0.03)was higher than that of the sham group(0.16 ± 0.02),and statistical significance could be noted,when comparisons were made(P<0.05).For the carvedilol group,the AOD level in the expression of GRP78 was significantly lower than that of the CIH group(0.20 ±0.02),but slightly higher than that of the shame group,also with statistical significance(P<0.05).(3)The AOD level in the expression of CHOP protein for the CIH group(0.45 ± 0.03)was higher than that for the sham group(0.05 ±0.02), and there was statistical significance when comparisons were made (P<0.05).The AOD level in the expression of CHOP protein for the carvedilol group(0.21 ±0.02)was significantly lower than that for the CIH group,but slightly higher than that for sham group, also with statistical significance(P<0.05).(4)Research results showed that apoptosis rate of myocardial cells for the CIH group [(16.31 ±1.96)%] was higher than that for the sham group[(2.40 ±0.88)%],and there was statistical significance when comparisons were made between them(P<0.05).The apoptosis rate of the carvedilol group(7.43 ±1.22%)was significantly lower than that of the CIH group,but slightly higher than that of the sham group, also with statistical significance(P<0.05).Conclusion Carvedilol could decrease GRP78 and CHOP expression levels of myocardial cells in hypertensive cardiomyocytes,and lower the level of endoplasmic reticulum stress(ERS), the protective mechanism of which might be associated with the intervention of ERS-mediated cardiomyocytes reconstruction.
