【Abstract】 0bjective To explore the effects of sarcoendoplasmic reticulum calcium ATPase2a(SERCA2a) overexpression on the protein expression of L-type voltage dependent calcium channel (LVDCCalc) subunit in the rabbit model of atrial fibrillation(AF). Methods Forty-eight New Zealand rabbits were randomized into four groups (n=12),including control group,AFgroup,rAAV9 EGFP AFgroupand rAAV9 SERCA2a EGFP AF group.rAAV9-EGFP and rAAV9-SERCA2a-EGFP(1.0?012v.g/礚 for each animal )were injected into pericardium of the animals of rAAV9 EGFP AF and rAAV9 SERCA2a (enhanced green fluorescent protein)EGFP AF groups before rapid atrial pacing thirty day. Thirty day after gene transfection,AF was induced by rapid atrial pacing(600 beats／min)for 24 hours in each animal of AF group,rAAV9 EGFP AF group and rAAV9 SERCA2a EGFP AF group .Each animal of control group was not paced,Animals were scarified to observe expression of the green fluorescent protein in the myocardial frozen section of rabbits in rAAV9 EGFP AF group under the inverted fluorescence microscope,to assess the right atrial tissue morphology and detect the expressions of SERCA2a protein and LVDCCalc protein in the right atrial tissue in each group by H E staining and immunohistochemistry at 24 hours after pacing. Results Compared with AF group and rAAV9 EGFP AF group(P<0.05),expressions of SERCA2a protein and LVDCCalc protein in the right atrium of rabbits in rAAV9 SERCA2a EGFP AF group was significantly upregulated,but there is no difference on expressions of SERCA2a protein and LVDCCalc protein in the right atrium of rabbit among rAAV9 SERCA2a EGFP AF group,AF group and rAAV9 EGFP AF group (P>0.05). Conclusions The atrial tissue transferred SERCA2a protein could significantly decrease the downregulation of the LVDCCalc protein expression in this rabbit model of AF and reverse acute AF electrical remodeling.