ABSTRACT
Objective To investigate the effect of 36 h continuous sleep deprivation(SD) on circadian clock gene expression in the rat liver and kidney and the alteration of urine biomarker levels.Methods Twelve rats were randomly divided into control group and SD group.An SD device was used to deprive the rats of sleep.After 36 h continuous SD, the abdominal cavity was exposed to obtain livers and kidneys, and RT-PCR and Western blotting were used to detect expression of clock genes.Then,the pelvic cavity was exposed to obtain urine, and the changes in bio-marker total bile acids(TBA) were tested with ELISA.Results Compared with the control group, the mRNA level of liver clock and bmal1 was obviously reduced in the SD-treated rats (P<0.05).However, no obvious change was found in the samples from the kidney.Sharp down-regulation of CLOCK and BMAL1 protein expression was also observed in the rat liver after SD treatment.Urine TBA content in SD treated rats was raised obviously (P<0.001), compared with control.Conclusion Thirty-six hours of continuous SD could result in deregulation of circadian clock gene and cholesterol metabolism disorder in the rat liver.TBA might be used as a noninvasive biomarker of liver injury under SD stress conditions.