Stephenson Richard, Horner Richard L
Departments of Zoology, University of Toronto, Ramsay Wright Building, 25 Harbord Street, Toronto, Ont., Canada M5S 3G5.
Respir Physiol Neurobiol. 2006 Dec;154(3):351-5. doi: 10.1016/j.resp.2006.02.007. Epub 2006 Mar 22.
This study tested the hypothesis that apnoea index would be greater during daytime sleep than nighttime sleep in the rat. Electroencephalogram and electromyogram were monitored via biotelemetry implant and respiration was measured using whole body plethysmography in six male rats in two separate 34h recording sessions per animal. Apnoeas were classified as "spontaneous" or "post-sigh". Daily average spontaneous apnoea index was 35 times greater (p<0.0001) during rapid eye movement (REM) sleep than in non-REM (NREM) sleep. In contrast, daily average post-sigh apnoea index was not significantly greater in REM sleep than in non-REM (NREM) sleep (p=0.39). There was a greater post-sigh apnoea index during daytime REM than during nighttime REM (p=0.043) but REM-related spontaneous apnoea index was unaffected by time of day. There was no day to night difference in spontaneous apnoea index or post-sigh apnoea index during NREM sleep. Respiratory variability (coefficient of variation for breath duration and tidal volume) was not affected by time of day in REM or NREM sleep. We conclude that the circadian timing system has no effect on apnoea index during NREM sleep in the rat, but it may influence the propensity for post-sigh apnoea during REM sleep.
本研究检验了大鼠白天睡眠时呼吸暂停指数高于夜间睡眠的假设。通过生物遥测植入监测脑电图和肌电图，并使用全身体积描记法测量六只雄性大鼠的呼吸，每只动物在两个单独的34小时记录时段内进行测量。呼吸暂停分为“自发性”或“叹气后”。快速眼动（REM）睡眠期间的每日平均自发性呼吸暂停指数比非快速眼动（NREM）睡眠期间高35倍（p<0.0001）。相比之下，REM睡眠期间的每日平均叹气后呼吸暂停指数并不显著高于非快速眼动（NREM）睡眠（p=0.39）。白天REM期间的叹气后呼吸暂停指数高于夜间REM（p=0.043），但与REM相关的自发性呼吸暂停指数不受一天中时间的影响。NREM睡眠期间自发性呼吸暂停指数或叹气后呼吸暂停指数没有昼夜差异。REM或NREM睡眠期间的呼吸变异性（呼吸持续时间和潮气量的变异系数）不受一天中时间的影响。我们得出结论，昼夜节律系统对大鼠NREM睡眠期间的呼吸暂停指数没有影响，但可能会影响REM睡眠期间叹气后呼吸暂停的倾向。
