2.2 HL-1 cell culture
HL-1 mouse atrial myocytes were maintained in Claycomb medium supplemented with 100 U/mL penicillin, 100 μg/mL streptomycin, and 100 μM norepinephrine in 30 mM L-ascorbic acid, 2 mM L-glutamine, and 10% FBS at 37°C in a humidified atmosphere of 5% CO2. To clarify the effects of isorhamnetin on atrial myocytes, HL-1 cells were seeded in a 6-well plate precoated with a solution of 0.02% (w/v) gelatin containing 5 μg/mL fibronectin. HL-1 cells were treated with AngІІ (1 μM) for 24 h with (AngII +isorhamnetin group) or without (AngII group) isorhamnetin. In the AngII+isorhamnetin group, cells were pretreated with isorhamnetin 1 h before AngII exposure. The cells were harvested for further analysis.