Abstract:
Sleep is an instinct behavior, and its significance and functions are still an enigma. It is expressed throughout one\'s life and its loss affects psycho-somatic and physiological processes. We had proposed that it might maintain a fundamental property of the neurons and the brain. In that context, it was shown that sleep, rapid eye movement sleep (REMS) in particular, by regulating noradrenaline (NA), maintains the brain excitability. It was also reported that sleep-loss affected memory, reaction time and decision-making ability among others. However, as there was lack of clarity on the cause-and-effect relationship as to how the sleep-loss could affect these basic behaviors, their association was questioned and it was difficult to propose a cure or at least ways and means to ameliorate the symptoms. Also, we wanted to conduct the studies in a simpler model system so that conducting future molecular studies might be easier. Hence, using zebrafish as a model we evaluated if sleep-loss affected the basic decision-making ability, a cognitive process and if the effect was induced by NA. Indeed, our findings confirmed that upon sleep-deprivation, the cognitive decision-making ability of the prey zebrafish was compromised to protect itself by running away from the reach of the exposed predator Tiger Oscar (TO) fish. Also, we observed that upon sleep-loss the axonal arborization of the prey zebrafish brain was reduced. Interestingly, the effects were prevented by prazosin (PRZ), an α1-adrenoceptor (AR) antagonist and when the zebrafish recovered from the lost sleep.
摘要:
睡眠是一种本能行为,它的意义和功能仍然是一个谜。它在人的一生中都有表达,它的丧失会影响心身和生理过程。我们已经提出,它可能保持神经元和大脑的基本属性。在这种情况下,它显示了睡眠,特别是快速眼动睡眠(REMS),通过调节去甲肾上腺素(NA),保持大脑的兴奋性。据报道,睡眠不足会影响记忆,反应时间和决策能力等。然而,由于缺乏对睡眠损失如何影响这些基本行为的因果关系的明确性,他们之间的联系受到质疑,很难提出治疗方法或至少是改善症状的方法。此外,我们希望在一个更简单的模型系统中进行研究,以便进行未来的分子研究可能更容易。因此,使用斑马鱼作为模型,我们评估了睡眠不足是否影响了基本决策能力,认知过程,如果效果是由NA诱导的。的确,我们的发现证实了在睡眠不足时,通过逃离暴露的捕食者TigerOscar(TO)鱼来保护自己,从而损害了猎物斑马鱼的认知决策能力。此外,我们观察到睡眠不足时,猎物斑马鱼大脑的轴突乔化减少。有趣的是,哌唑嗪(PRZ)预防了这种作用,α1-肾上腺素受体(AR)拮抗剂,当斑马鱼从失去的睡眠中恢复时。