Figure 5.

Knockdown of Nur77 attenuates ISO-induced RLN3 expression in cardiomyocytes. A, NRVMs were transfected with 30 nm either Nur77 siRNA (siNur77) or control siRNA (siCTL). 72 h after transfection, the expression of Nur77 was determined by Western blotting (n = 4). *, p < 0.05 compared with siCTL. B, NRVMs were transfected with 30 nm either siNur77 or siCTL. 72 h after transfection, cells were stimulated with the indicated concentrations of ISO for 6 h. The expression of RLN3 was then determined by qRT-PCR (n = 4). *, p < 0.05 compared with ISO at 0 μm. C, Nur77 knockdown attenuated ISO-induced RLN3 levels in the supernatants of cardiomyocytes. NRVMs were transfected with 30 nm either siNur77 or siCTL. 48 h after transfection, cardiac cells were stimulated with 10 μm ISO for 48 h. The levels of RLN3 in the supernatants were determined by ELISA (n = 4). *, p < 0.05 compared with cardiomyocytes transfected with siCTL. D, adult WT and Nur77 knockout mice (Nur77 KO) were treated with a single intraperitoneal injection of ISO (1 mg/kg) or 0.9% saline (Veh), and 12 h after injection of ISO, the hearts were harvested for extraction of total RNAs. The expression of RLN3 was then determined by qRT-PCR. *, p < 0.05 versus saline-treated WT mice (Veh); #, p < 0.05 versus ISO-treated WT mice. The data represent three independent experiments with five mice in each group. Error bars, S.D.