NOS2 and atrial fibrillation: Moreover, the variable importance in projection (VIP) indicated that cholesterol, TG, AST, ALT, WBCs, lymphocytes, MDA, iNOS mRNA, NF-κB/p65 mRNA, TNF-α mRNA, IL-6 mRNA, Casp3 protein, Cyto c protein, and IL-6 protein were the most influential variables in the discrimination of AF-treated animals from the rest (Figure 6B).