Objective: To explore the possible mechanism and effect of tanshinoneⅡA on the protein expression of L-type calcium channelα1c in th rat atrial fibrillation model to reveal the mechanism of AF. Method: Rats were randomly divided into four groups

normal control group

model group

tanshinone ⅡA group and Verapamidronate group.The rat atrial fibrillation model was established by the tail vein injection of acetylcholine a calcium chloride (Ach-CaCl2) drug. The change of LTCCα1c expression was detected with immunohistochemistry after two weeks. Result: Compared with normal control group

in model group CaLα1c subunit mRNA expression level was reduced

L calcium channel (LTCC) protein expression level was reduced

there was a difference between two groups (P<0.05);compared with model group

in tanshinone treatment group and verapamil intervention group atrial fibrillation rats and atrial organization were significantly improved. CaLα1c subunit mRNA expression and protein expression level were reduced (P<0.05). Conclusion: TanshinoneⅡA could improve the decreasing status in AF rats and atrial muscle cell reconstruction process of the damage degree

which may be related with. CaLα1c subunit mRNA expression and protein expression.