Effect of telmisartan on levels of serum adiponectin and expression of cardiac adiponectin receptor 1 in spontaneously hypertensive rats
10.3760/cma.j.issn.0254-9026.2011.01.016
- VernacularTitle:替米沙坦对自发性高血压大鼠血清脂联素及心肌脂联素受体1表达的影响
- Author:
Shupo LIN
;
Jie LIN
;
Xiaoyi ZHANG
;
Jin SHI
- Publication Type:Journal Article
- Keywords:
Rat,inbred SHR;
Adiponectin;
Ventricular remodeling
- From:
Chinese Journal of Geriatrics
2011;30(1):59-64
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo observe the effect of telmisartan on the level of serum adiponectin and the expression of cardiac adiponectin (APN) receptor 1 in spontaneously hypertensive rats (SHR) in order to explore the role of APN in ventricular remodeling caused by hypertension and the new possible mechanism that telmisartan protects the heart against ventricular remodeling.Methods The sixteen 12-week-old SHR were randomly divided into SHR control group (SHR group, n=8) and SHR+telmisartan group (TEL group, n=8), and eight age-matched male Wistar Kyoto rats were regarded as control group (WKY group). The TEL group was treated with telmisartan 5 mg-1 · kg-1 ·d-1 in a small amount of distilled water and the other two groups were given equal amount of distilled water by gavage.After 8 weeks, the left ventricular end diastolic diameters (LVEDD),thickness of interventricular septal thickness (IVST), left ventricular post wall thickness (LVPWT) and mitral valve blood flow spectrums were recorded by echoeardiograph.The E/A ratio was calculated by velocity of E peak divided by A peak. The left ventricular weight index (LVWI) was calculated. HE staining and Masson staining were used to detect the pathology changes of cardiac tissue and collagen volume fraction (CVF).Serum APN concentration of SHR was detected by enzyme-linked immunosorbent assay (ELISA). The myocardial protein expression of AdipoR1 was detected by in munohistochemical staining.Reverse transcription polymerase chain reactions (RTPCR) method was used to detect the mRNA expression of AdipoRl in myocardium.ResultsThe values of IVST, LVPWT and LVWI were higher, LVEDD and E/A ratio were lower in SHR group than in WKY group.The disordered arrangement of myocardialcells,interstitialfibroblast hypertrophy and hyperplasia were observed in SHR group. The CVF increased in SHR group than in WKY group [(6.22±0.16)％ vs. (3. 18±0. 17)％, P＜0.05]. The concentration of serum APN was significantly lower in SHR group [( 10.96±2. 15)μg/ml vs. (24.32±2. 20)μg/ml, P＜0. 01].The expressions of myocardial AdipoR1 mRNA and protein were significantly lower in SHR group.The values of IVST, LVPWT and LVWI were lower, LVEDD and E/A ratio were higher in TEL group than in SHR group. The arrangement of myocardial cells were relatively ordered and interstitial fibroblasts hypertrophy and hyperplasia were not significant, CVF was decreased in TEL group versus SHR group. The concentration of serum APN was significantly higher in TEL group [(17.71 ± 5.82)μg/ml, P＜0. 01]. The expressions of myocardial AdipoR1 mRNA and protein were significantly higher in TEL group than in SHR group. Conclusions When SHR undergoes ventricular remodeling, the level of serum APN is lower, the mRNA and protein expressions of myocardial AdipoRl are significantly reduced. Telmisartan can reverse the ventricular remodeling and play the role in protecting heart in SHR, which may be due to the serum APN levels increasing, cardiac APN receptor 1 and its mRNA up-regulation.
