Melatonin is an important pineal hormone that regulates human and animal circadian rhythms and sleep. Mounting clinical and rodent evidence indicates that melatonin also modulates affective behaviors and cognition. The zebrafish (Danio rerio) is rapidly becoming a powerful novel model organism in translational neuroscience research. Here, we evaluate the effects of a 24-h melatonin treatment on behavior and physiology of adult zebrafish with circadian rhythm disturbed by a 24-h light exposure. While such light exposure evoked overt cognitive and neuroendocrine (cortisol) deficits in zebrafish, these effects were reversed by a 24-h melatonin treatment. Collectively, these findings suggest a positive modulation of affective and cognitive phenotypes in zebrafish by melatonin, and reinforce the growing utility of zebrafish models for studying circadian, cognitive and behavioral processes and their neuroendocrine regulation in vivo.

褪黑素是一种重要的松果激素，可调节人和动物的昼夜节律和睡眠。大量的临床和啮齿动物证据表明，褪黑激素还可以调节情感行为和认知。斑马鱼（Danio rerio）正迅速成为转化神经科学研究中一种功能强大的新型模型生物。在这里，我们评估了24小时褪黑素治疗对成年斑马鱼的行为和生理的影响，其昼夜节律受到24小时光照的干扰。虽然这种光照引起了斑马鱼明显的认知和神经内分泌（皮质醇）缺乏症，但通过24小时褪黑素治疗可以逆转这些影响。总的来说，这些发现表明褪黑激素对斑马鱼的情感和认知表型有积极的调节作用，并增强了斑马鱼模型在研究昼夜节律，认知和行为过程及其体内神经内分泌调节方面的实用性。