Beaulé Christian, Barry-Shaw Jane, Amir Shimon
Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, Quebec, H4B 1R6, Canada.
J Mol Neurosci. 2004;22(3):223-30. doi: 10.1385/JMN:22:3:223.
The protein product of the immediate-early gene c-fos is expressed rhythmically in the shell region of the suprachiasmatic nucleus (SCN), the mammalian circadian clock. Recently, we found that exposure to an entraining light pulse caused a suppression of Fos expression in the SCN shell in rats. To study the hypothesis that suppression of Fos in the shell is a correlate of photic entrainment, we used rats that were treated with the retinal neurotoxin monosodium glutamate (MSG) during the neonatal period. In spite of retinal degeneration, MSG-treated rats entrained normally and displayed light-induced suppression of Fos within the SCN shell. These results support the view that light-induced suppression of Fos within the SCN shell is a cellular correlate of photic entrainment.
即刻早期基因c-fos的蛋白质产物在哺乳动物生物钟视交叉上核（SCN）的壳区有节律地表达。最近，我们发现给予大鼠一个同步光脉冲会导致SCN壳区Fos表达受到抑制。为了研究壳区Fos抑制是光同步化的一个相关因素这一假说，我们使用了在新生期用视网膜神经毒素谷氨酸单钠（MSG）处理过的大鼠。尽管视网膜发生了退化，但经MSG处理的大鼠仍能正常同步化，并在SCN壳区内表现出光诱导的Fos抑制。这些结果支持了这样一种观点，即SCN壳区内光诱导的Fos抑制是光同步化的细胞相关因素。
