Immunofluorescence staining revealed a decrease in the expression levels of gap junction protein Cx43 in the left atrial tissue of rats in the AF group, accompanied by redistribution among cells (Figures 8G,I), suggesting that SLFM could counteract the downregulation of Cx43 expression, with SLFM-H demonstrating a more pronounced effect. This evidence concerns the gene GJA1 and atrial fibrillation.