Food-entrained circadian rhythms in rats are insensitive to deuterium oxide
Food-entrained circadian rhythms in rats are insensitive to deuterium oxide
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DOI：
10.1016/s0006-8993(01)03042-6
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发表时间：
2001-11-23
期刊：
影响因子：
2.9
通讯作者：
Kippin, TE
中科院分区：
文献类型：
--
作者：
Mistlberger, RE;Marchant, EG;Kippin, TE
大鼠通过携带与位于视交叉上核（SCN）的可光携带昼夜节律起搏器分离的昼夜节律起搏器来预测预定的每日肉类。食物可携带起搏器的位置和分子机制尚不清楚。氘化显著延长了SCN起搏器的内在周期（tau）。在完整和scn消融的大鼠中评估了食物携带的昼夜节律对D2O（饮用水中25%）的敏感性。在自由进食的完整大鼠中，D2O延长了tau蛋白，足以使活动节律脱离光-暗循环的束缚。相比之下，食物携带的节律令人惊讶地抵抗D2O的调节。完全scn消融的大鼠的平均每日食物预期活动开始时间不受D2O摄入长达28天的影响。在D2O治疗期间，在完整和部分scn消融的大鼠中，预期活动的短暂延迟和中断是明显的，但这些可以解释为D2O敏感的光携带起搏器和D2O抗性食物携带起搏器之间的耦合和/或掩盖相互作用的影响。哺乳动物对D2O的不同敏感性表明食物和光诱导的昼夜节律起搏器的分子机制存在差异。D2O可能有筛选的作用。该测试旨在从那些能够表达独立于SCN的时钟基因的昼夜节律振荡的中央和外周组织中确定假定的食物可携带的起搏器。(C) 2001 Elsevier Science B.V.版权所有
Rats anticipate a scheduled daily meat by entrainment of a circadian pacemaker separate from the light-entrainable circadian pacemaker located in the suprachiasmatic nuclei (SCN). The site and molecular mechanisms of the food-entrainable pacemaker are unknown. The intrinsic period (tau) of the SCN pacemaker is significantly lengthened by deuteriation. Sensitivity of food-entrained circadian rhythms to D2O (25% in drinking water) was evaluated in intact and SCN-ablated rats entrained to daily feeding schedules. In intact rats fed ad-libitum, D2O lengthened tau sufficiently to drive activity rhythms out of entrainment to the light-dark cycle. By contrast, food-entrained rhythms were surprisingly resistant to modulation by D2O. The mean daily onset time of food anticipatory activity in rats with complete SCN-ablations was not affected by up to 28 days of D2O intake. Transient delays and disruption of anticipatory activity were evident in intact and one partial SCN-ablated rat during D2O treatment, but these are interpretable as effects of coupling and/or masking interactions between a D2O-sensitive light-entrainable pacemaker, and a D2O-resistant food-entrained pacemaker. Differential sensitivity to D2O suggests diversity in the molecular mechanisms of food- and light-entrainable circadian pacemakers in mammals. D2O may have utility as a screening., test to identify putative food-entrainable pacemakers from among those central and peripheral tissues that can express circadian oscillations of clock genes independent of the SCN. (C) 2001 Elsevier Science B.V. All rights reserved.