Over-expression of SK2 channel in PVN reduces renal sympathetic nerve activity in chronic heart failure rats
10.3969/j.issn.1000-4718.2014.08.024
- VernacularTitle:下丘脑室旁核小电导钙激活钾通道过表达降低慢性心衰大鼠肾交感神经兴奋性
- Author:
Xiaoyan LI
;
Jinling LIU
;
Le GUI
;
Jianhua ZHU
- Publication Type:Journal Article
- Keywords:
Hypothalamus paraventricular nucleus;
Small-conductance calcium-activated potassiumchannel subtype 2;
Heart failure
- From:
Chinese Journal of Pathophysiology
2014;(8):1478-1482
- CountryChina
- Language:Chinese
-
Abstract:
[ABSTRACT]AIM:Toinvestigatetheeffectofover-expressionofsmall-conductancecalcium-activatedpotassium channel subtype 2 (SK2) in the paraventricular nucleus (PVN) of hypothalamus on heart rate(HR), mean arterial pres-sure (MAP) and renal sympathetic nerve activity (RSNA) of the rats with chronic heart failure (CHF).METHODS:Adenovirus vector encoding SK2 (pDC316-mCMV-EGFP-rKCNN2) was constructed.The CHF model of the male Sprague Dawley ( SD) rats was established by the ligation of anterior descending coronary artery .Echocardiogram was used at the 6th week after the operation to identify the CHF model .Adenovirus vector encoding SK 2 ( pDC316-mCMV-EGFP-rKCNN2) or control adenovirus vector ( pDC316-mCMV-EGFP) were transfected into the PVN in vivo.The cardiac func-tion was monitored by echocardiogram .The expression of SK2 at mRNA and protein levels was determined by RT-PCR, Western blotting and immunofluorescence .The HR, MAP and RSNA were measured by PowerLab 8/30 in anesthetized rats with bilateral PVN microinjection of SK channel blocker apamin .RESULTS:Treatment with pDC316-mCMV-EGFP-rKC-NN2 significantly decreased the renal sympathetic nerve activity in the rat with CHF .Injection of pDC316-mCMV-EGFP did not change the renal sympathetic nerve activity in the rats in sham group .CONCLUSION:The expression and func-tion of SK channels in PVN in the heart failure rats were decreased , suggesting a reduced negative regulation of sympathetic activity in central neural system .Increased expression of SK 2 in the PVN leads to a reduction in sympathetic outflow under the condition of CHF , which may provide a new target for the treatment of heart failure .
