KCNA5 and atrial fibrillation: Additionally, uric acid (UA)-induced upregulation of Kv1.5 expression may represent a novel mechanism for the induction of atrial fibrillation: UA enhances Kv1.5 protein expression by activating the ERK pathway and promoting the expression of Heat Shock Protein 70 (Hsp70) in mouse atrial myocytes (HL-1 cells), thereby increasing the ultra-rapid delayed rectifier K+ current and shortening the duration of action potentials (39, 40).