Zlomanczuk P, Margraf R R, Lynch G R
Department of Biology, Wesleyan University, Middletown, CT 06459-01700.
Brain Res. 1991 Sep 13;559(1):94-9. doi: 10.1016/0006-8993(91)90291-3.
Djungarian hamsters (Phodopus sungorus sungorus) were chronically exposed to constant light (60 lux) in order to generate a split rhythm of wheel-running behavior. The animals were killed and coronal hypothalamic slices prepared for extracellular recording from the left and right suprachiasmatic nuclei (SCN). Nine hamsters which exhibited a split in overt behavior also had bimodal peaks (280 cells) of SCN firing frequency (5.4 +/- 1.1 and 5.8 +/- 0.7 Hz); these peaks were about 180 degrees antiphase. Two troughs in firing frequency were also apparent (1.8 +/- 0.4 and 2.4 +/- 0.5 Hz) and coincided with the projected time of wheel-running activity. Differences in circadian pattern of electrical activity between the right and left SCN were not observed. When wheel-running activity in 5 hamsters was suppressed with high intensity (500 lux) constant light, the SCN firing profile (154 cells) failed to exhibit a daily rhythm. Firing frequency was consistently high (5.8 +/- 1.4 Hz) throughout the 24-h period. These results indicate that in vitro electrical activity of the SCN is related to overt behavior in Djungarian hamsters, in that high electrical activity occurs when locomotor activity is minimal.
将黑线毛足鼠（Phodopus sungorus sungorus）长期暴露于持续光照（60勒克斯）下，以产生转轮行为的分裂节律。处死动物并制备下丘脑冠状切片，用于从左右视交叉上核（SCN）进行细胞外记录。9只表现出明显行为分裂的仓鼠，其SCN放电频率（5.4±1.1和5.8±0.7赫兹）也有双峰（280个细胞）；这些峰大约呈180度反相。放电频率的两个谷值也很明显（1.8±0.4和2.4±0.5赫兹），并且与预计的转轮活动时间一致。未观察到左右SCN之间电活动昼夜模式的差异。当用高强度（500勒克斯）持续光照抑制5只仓鼠的转轮活动时，SCN放电曲线（154个细胞）未表现出每日节律。在整个24小时期间，放电频率始终较高（5.8±1.4赫兹）。这些结果表明，SCN的体外电活动与黑线毛足鼠的明显行为有关，即当运动活动最少时，电活动较高。
