Kv1.5 is expressed in the brain (hippocampus, pituitary, microglia, oligodendrocytes and Schwann cells) as well as kidney, colon, aorta, pulmonary artery and smooth muscle. This ion channel is involved in the maintenance of the resting membrane potential and therefore regulates the activity electrically excitable cells. Kv1.5 is potentially a target for the management of atrial fibrillation. Since they are not found in the ventricles, drugs selective for this channel may be beneficial in the treatment of atrial fibrillation without the risk of causing ventricular arrhythmias. Apart from these instances where the purpose is to develop a cardiovascular drug targeted to Kv1.5, an interaction of lead development compounds with this channel is best avoided. This is due to the fact that the channel has such a widespread distribution and controls membrane excitability.