Evaluation of the effect of 17β-estradiol on right ventricular function in a rat model of pulmonary arterial hypertension by echocardiography

Abstract

Objective To evaluate right ventricular (RV) function in male rats with pulmonary arterial hypertension (PAH) induced by Monocrotaline (MCT) and discuss the effect of 17β-estradiol (E2) on RV function in PAH rats. Methods Thirty-two male SD rats were randomly divided into 4 groups(n=8): MCT group, MCT+ E2 group, MCT+ Veh group and control group. MCT group, MCT+ E2 group and MCT+ Veh group were given monocrotaline through intraperitoneal injection. MCT+ E2 group and MCT+ Veh group were also treated with E2 and placebo at the same time respectively. Echocardiography was performed four weeks later after MCT injection. Right heart catheterization was performed after echocardiography. Echocardiography right ventricular function parameters included: tricuspid annular plane systolic excursion (TAPSE), RV index of myocardial performance (RIMP), right ventricular fractional area change (RVFAC), tissue Doppler-derived tricuspid lateral annular systolic velocity (s′) and right ventricular free wall longitudinal strain (RVLSFW). Results Compared with control group, TAPSE, RVFAC and RVLSFW decreased, and RIMP increased in MCT group, (P 0.05). Moreover, Pearson correlation analysis showed that the serum E2 level was positively correlated with TAPSE, RVFAC, s′ and RVLSFW(r=0.845, P<0.001; r=0.859, P<0.001; r=0.802, P=0.006, respectively), and negatively correlated with RIPM(r=-0.803, P<0.001). Conclusions RV function in male PAH rats induced by MCT decreased significantly, while E2 could improve RV function in PAH rats and has a protective effect on RV function. Echocardiography could contribute to the quantitative evaluation of RV function in PAH rats induced by MCT. Key words: Echocardiography; Hypertension, pulmonary; Ventricular function, right; Estradiol; Rat