Effects of a Brief Light Pulse and Intracerebroventricular Injection on Sleep-Wake Activity in Rats

光照與側腦室注射對睡眠之影響

尹珮璐(Pei-Lu Yi) ； 蔡崇豪(Chon-Haw Tsai) ； 呂明桂(Ming-Kuei Lu) ； 陳雅筑(Ya-Ju Chen) ； 楊玉婉(Yu-Wan Yang) ； 張芳嘉(Fang-Chia Chang)

《Mid-Taiwan Journal of Medicine》 9卷4期 (2004/12) Pp. 211-218

https://doi.org/10.6558/MTJM.2004.9(4).3

摘要

目的　十二小時光照期/十二小時黑暗期的重複性週期是維持一定睡眠週期的重要因素。我們先前的結果顯示在光照期/黑暗期的中點於側腦室給予促腎上腺皮質激素釋放激素(corticotropin-releasing hormone, CRH)的反意核酸(antisense oligodeoxynucleotide)會改變老鼠的睡眠，然而由於在側腦室注射時會有光照與注射本身等因素對睡眠的作用，因此在本實驗要來進一步探討光照與側腦室注射本身對睡眠的作用。
方法　大白鼠經過手術後安裝了腦波電極以及側腦室注射的導管，並讓老鼠適應十二小時光照期/十二小時黑暗期的重複性週期。一組未經操作的老鼠在光照期或黑暗的中點側腦室注射生理食鹽水普記錄睡眠的變化。
結果　結果顯示在黑暗期的中點給予短暫的光照，在未經操用的老鼠中會在給予光照的那一小時內明顯的增加慢速波睡眠及減少快速動眼期睡眠，但不會改變大腦皮質的溫度。在經過適應期的老鼠中，給予光照及側腦室注射生理食鹽水，會在給予的那一小時內顯著的減少慢速波睡眠及快速動眼期睡眠的量，並在接下來的一、二小時會回複增加慢速波睡眠及快速動眼期睡眠的量；另外，大腦皮質溫度亦會在側腦室注射生理食鹽水時增加。
結論　目前的結果顯示當在光照期或黑暗的中點給予光照及側腦室注射生理食鹽水對於經過適應期的老鼠依然是某種程度的壓力，而這種壓力會複蓋過光照本身對於睡眠的影響。

關鍵字

光照 ； 壓力 ； 睡眠

並列摘要

Objectives The light/dark (L/D) cycle is an important regulator of the circadian rhythm of sleep-wake activity and neuroendocrine fluctuation. We previously reported that the intracerebroventricular (ICV) injection of corticotropin-releasing hormone (CRH) antisense oligodeoxynucleotide during the middle of the dark period altered spontaneous waking; however, it is believed that either the light pulse during the ICV injection or the injection per se in the middle of the L/D period may disturb circadian rhythm of rats. The purpose of this study was to further elucidate the effects of ICV injection and the light pulse given during the dark period and during the light period on sleep-wake activity.
Methods. Male Sprague-Dawley rats were implanted with electroencephalogram (EEG) electrodes and an ICV guide cannula. Rats were accustomed to a 12/12h L/D cycle. Na rats received a 5-mm period of light flash either in the middle of the light period or in the middle of the dark period, whereas the well-habituated rats received a light pulse and ICV injection of pyrogen-free saline (PFS) either in the middle of the light period or in the middle of the dark period.
Results In naïve rats, the 5-mm period of light pulse given during the dark period of the L/D cycle significantly enhanced slow wave sleep (SWS) and decreased rapid eye movement sleep (REMS) during the hour when the light flashed. Sleep was not altered when the light pulse occurred during the light period. There was no change in brain temperature. In well-habituated rats, the light pulse with ICV injection of PFS decreased SWS and REMS during the hour when the manipulation was given; during the subsequent 12-h period, the SWS and REMS significantly rebounded. Brain temperature increased after ICV injection.
Conclusions. Our results indicate that injection and handling, which are considered to be stressors to rats, either during the middle of light period or during the middle of the dark period, mask the effect of light pulse on sleep-wake activities.

並列關鍵字

light flash ； stress ； sleep