Eukaryotic expression vector pcDNA3-HERG transfection inhibits angiotensin Ⅱ induced neonatal rabbit ventricular myocyte hypertrophy in vitro
10.3760/cma.j.issn.0253-3758.2009.10.017
- VernacularTitle:真核表达质粒pcDNA3-HERG转染抑制血管紧张素Ⅱ诱导乳兔心肌细胞肥大
- Author:
Yong-Hui ZHAO
1
;
Chang-Cong CUI
;
Yu LI
;
Chen HUANG
Author Information
1. 河南省人民医院
- Keywords:
Myocytes;
cardiac;
Hypertrophy;
Angiotensin Ⅱ;
Plasmids;
Transfection
- From:
Chinese Journal of Cardiology
2009;37(10):931-935
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effects of eukaryotic expression vector pcDNA3-HERG transfection on angiotensin Ⅱ ( Ang Ⅱ) induced myocyte hypertrophy in cultured neonatal rabbit ventricular myocytes. Methods Neonatal rabbit ventricular myocytes and eukaryotic expression vector pcDNA3-HERG transfected ventricular myocytes were cultured in Dulbecco's-modified Eagle medium (DMEM), containing 1% fetal bovine serum (FBS) for 6 h, then stimulated with Ang Ⅱ (10~(-7) mol/L) for 48 h. Control ventrictdar myocytes were cultured in Dulbecco's-medified Eagle medium (DMEM), containing 1% fetal bovine serum (FBS) for 54 h. At 6 and 54 h, myocyte hypertrophic parameters including myocyte volume, total protein content and membrane capacitance, action potential duration (APD) and Calcineurin (CaN) activity were measured. Results Compared to control myocytes, APD at 90% repolarization ( APD_(90)) was prolonged by 19. 8% (P<0.01), without signs of myocyte hypertrophy at 6 h post Ang Ⅱ stimulation, APD_(90) was prolonged by 22.1% (P<0.01), myecyte volume, total protein content and membrane capacitance and CaN activity were significantly increased by 40.4%, 40.4%, 38.2% and 114.7% respectively (all P<0.01 ) at 48 h after Ang Ⅱ stimulation. HERG gene transfection upregnlated I_(HERG) tail current (3.6-fold higher than I_(Kr), -rapidly activating delayed rectifier potassium current,P<0.01). HERG gene transfection also accelerated and replarization and asbortened APD_(90) and inhibited myocyte hypertrophy and CaN activation induced by Ang Ⅱ. Conclusions Ang Ⅱ induced prolongation of APD_(90) is directly associated with myecyte hypertrophy by increasing the Ca~(2+) influx and resulting in the increment of intracellular Ca~(2+) and activation of CaN reaction pathway.
