光照对大鼠外周血淋巴细胞生物钟相关基因表达的影响

目的 探讨光照对机体外周血淋巴细胞钟基因clock及褪黑素膜受体基因(mt1和mt2)表达的影响,为生物钟应用于临床提供基础依据.方法 将100只Sprague-Dawley大鼠随机分为2组,分别在全黑暗和光照-黑暗交替(12:12)条件下饲养.6周后用活动度测定仪筛选昼夜节律表现比较一致的大鼠,每组36只,再根据不同检测时间点随机分6个亚组,每个亚组6只,继续于相应光照条件下(全黑暗和光照黑暗交替)饲养1周后,收集外周血淋巴细胞.用半定量逆转录聚合酶链反应(RT-PCR)法检测生物钟相关基因clock、mt1和mt2的变化,用余弦软件进行节律特征分析,并比较在两种光照条件下基因表达的节律变化.结果 在全黑暗光制下,clock、mt1和mt2均呈节律性表达,其峰值相位分别位于CT7、CT9和CT11;在光照-黑暗交替(12:12)光制下,各基因表达的节律特征发生了变化,峰值相位分别为ZT21、ZT8和ZT6.在不同光制下,基因表达的强度和振幅有所不同.结论 光照能影响外周血淋巴细胞钟基因clock及相关基因的表达,光照可能通过clock对mt1和mt2的表达节律起调节作用.

Effects of light on the expression patterns of circadian clock-related genes in the peripheral lymphocytes

Objective To explore the effects of light on the expression patterns of clock and clock-related genes in peripheral lymphocytes.To develop basic knowledge needed for clinical application of the circadian clock.Methods One hundred Sprague-Dawley rats were housed under constant dark(DD)or normal light-dark(LD 12:12)conditions for six weeks.Peripheral iymphoeytes were collected at different time points.The expression level of the clock gene and melatonin receptor genes mt1 and mt2 were detected using semi-quantitative RT-PCR.The data were analyzed with cosine software.Results Circadian expression of the genes was observed in both groups,but the peak phase,amplitude and strength of expression of each gene differed with the light conditions.Conclusion Light influences the expression of clock and clock-related genes in rats' peripheral lymphocytes.The clock gene might play an important role in regulating the expression of mt1 and mt2.