Gökmen Necati, Barış İbrahim, Öçmen Elvan, Yılmaz Osman, Günerli Ali, Kavaklı İbrahim Halil
Department of Anesthesiology and Reanimation, Dokuz Eylül University School of Medicine, İzmir, Turkey.
Molecular Biology and Genetics, Koç University, İstanbul, Turkey.
Turk J Anaesthesiol Reanim. 2017 Aug;45(4):197-202. doi: 10.5152/TJAR.2017.68466. Epub 2017 Aug 1.
The aim of this study is to investigate the effects of light and administration time of isoflurane on circadian gene expression in the brains and liver tissues of rats kept in light-dark cycle.
Seventy two 15-days-old rats pups were divided into four groups. All animals were exposed to 1.5% concentration of isoflurane or to 6 L min O for six hours between Zeitgeber Time (ZT) 0-ZT06 (day-time administration) or ZT12-ZT18 (night-time administration). Rats were sacrificed after six hours of anaesthesia with four-hour time intervals. Total RNA was isolated from brains and liver tissues. Circadian gene expression was examined using quantitative real-time Reverse transcription polymerase chain reaction (RT-PCR).
BMAL1, CLOCK, PER2 and CRY2 gene expression levels were markedly suppressed after day-time anaesthesia in the both brain and liver, but night-time administration caused only temporary suppression of gene expression.
The effect of isoflurane on the circadian clock is time-dependent, and administered isoflurane anaesthesia at night had minimal effect on clock gene expression. Additionally, when the treated animals were kept in a regular light-dark cycle, isoflurane-induced phase shift was not observed, possibly because of the light.
本研究旨在探讨光照和异氟烷给药时间对处于昼夜节律周期的大鼠脑和肝组织中昼夜节律基因表达的影响。
将72只15日龄的幼鼠分为四组。所有动物在生物钟时间（ZT）0-ZT06（白天给药）或ZT12-ZT18（夜间给药）期间，暴露于1.5%浓度的异氟烷或6L/min的氧气中6小时。麻醉6小时后，每隔4小时处死一批大鼠。从脑和肝组织中提取总RNA。使用定量实时逆转录聚合酶链反应（RT-PCR）检测昼夜节律基因的表达。
白天麻醉后，脑和肝中BMAL1、CLOCK、PER2和CRY2基因的表达水平均显著受到抑制，但夜间给药仅导致基因表达的暂时抑制。
异氟烷对昼夜节律时钟的影响具有时间依赖性，夜间给予异氟烷麻醉对时钟基因表达的影响最小。此外，当处理后的动物处于正常的昼夜节律周期时，未观察到异氟烷诱导的相位偏移，这可能是由于光照的原因。
