DO HUMAN ATRIAL 5-HT4 RECEPTORS MEDIATE ARRHYTHMIAS

Since their first description five years ago, knowledge about human at rial 5-NT4 receptors has increased considerably. Progress has been fac ilitated by the advent of selective antagonists with high affinity for human atrial 5-HT4 receptors. The receptors have been detected in bot h right and left atrium where they mediate increases in contractile fo rce. Human sinoatrial 5-HT4 receptors may mediate the tachycardia caus ed by 5-HT and cisapride, and 5-HT elicits arrhythmias via 5-HT4 recep tors in human atrium. In this article, Alberto Kaumann suggests that 5 -HT may be involved in the genesis of atrial fibrillation acid associa ted thromboembolic stroke and that both the arrhythmia and stroke coul d be prevented by inhibiting 5-HT4 receptors.