摘要
Objectives To observe the expression of β3-adrenoceptor (β3-AR) of left ventricle and the effect on heart function by stimulating β3-AR in rats with experimental heart failure. Methods Rats were randomly divided into heart failure group and control group. Heart failure models were built up by ligating coronary artery in rats. The expression of β3-AR mRNA were detected with RT-PCR; The change of heart function were observed after administration of BRL37344 (β3-AR agonist) by measuring left ventricular end-systolic pressure (LVESP), left ventricular end-diastolic pressure (LVEDP), the maximum pressure ascending rate of left ventricle (+dp/ dtmax) and the maximum pressure descending rate of left ventricle(-dp/dtmax). Results The expression of β3-AR mRNA (β3/β-actin) was 0.028±0.005 and the proportion of β3-AR (β3/β1+β2+β3) was 5.4%±0.06% in failure rats while the expression of β3-AR mRNA was 0.011 ±0.004 and the proportion was 1.2%±0.04% in control rats; The descending percentage of LVESP, + dp/dtmax and -dp/dtmax were 16.1%, 21.7% and 13.2% respectively with administration of BRL37344 in failure rats, while 12.2%, 15.8% and 11.5% in control rats. Conclusions Compared with control group the expression of β3-AR mRNA of left ventricle was obviously increased and the negative inotropic function with exciting β3-AR was obviously enhanced in failure groups.
Objectives To observe the expression of β3-adrenoceptor (β3-AR) of left ventricle and the effect on heart function by stimulating β3-AR in rats with experimental heart failure. Methods Rats were randomly divided into heart failure group and control group. Heart failure models were built up by ligating coronary artery in rats. The expression of β3-AR mRNA were detected with RT-PCR; The change of heart function were observed after administration of BRL37344 (β3-AR agonist) by measuring left ventricular end-systolic pressure (LVESP), left ventricular end-diastolic pressure (LVEDP), the maximum pressure ascending rate of left ventricle (+dp/ dtmax) and the maximum pressure descending rate of left ventricle(-dp/dtmax). Results The expression of β3-AR mRNA (β3/β-actin) was 0.028±0.005 and the proportion of β3-AR (β3/β1+β2+β3) was 5.4%±0.06% in failure rats while the expression of β3-AR mRNA was 0.011 ±0.004 and the proportion was 1.2%±0.04% in control rats; The descending percentage of LVESP, + dp/dtmax and -dp/dtmax were 16.1%, 21.7% and 13.2% respectively with administration of BRL37344 in failure rats, while 12.2%, 15.8% and 11.5% in control rats. Conclusions Compared with control group the expression of β3-AR mRNA of left ventricle was obviously increased and the negative inotropic function with exciting β3-AR was obviously enhanced in failure groups.