Mistlberger R E
Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada.
Behav Neurosci. 1992 Feb;106(1):192-202. doi: 10.1037//0735-7044.106.1.192.
This study examined the role of the suprachiasmatic nuclei (SCN) in nonphotic entrainment. The wheel-running activity of SCN-ablated hamsters was recorded in constant dark (DD) and then under prolonged schedules of 2-hr daily cage changes, restricted food availability, and daily light-dark (LD) cycles. Some hamsters with very large lesions subsuming the SCN and surrounding areas exhibited significant, albeit unstable, circadian activity rhythms in DD. Some hamsters with similar ablations also showed entrained rhythms to daily cage change schedules. All hamsters showed robust rhythms entrained to a daily feeding schedule, but no hamsters showed entrainment to LD cycles. Competent circadian oscillators evidently exist outside the SCN, at least 0.5 mm or more away, and at least some are nonphotically entrainable. Weaker entrainment in animals with larger lesions suggests that nonphotically entrainable oscillators also exist within the SCN or its immediate vicinity.
本研究考察了视交叉上核（SCN）在非光信号同步化中的作用。在持续黑暗（DD）条件下记录了SCN被损毁的仓鼠的转轮活动，随后在每天2小时的长时间换笼、食物供应受限以及每日明暗（LD）循环的条件下进行记录。一些SCN及其周围区域有非常大损伤的仓鼠在DD条件下表现出显著的、尽管不稳定的昼夜节律活动。一些有类似损毁的仓鼠对每日换笼时间表也表现出同步化节律。所有仓鼠对每日喂食时间表都表现出强烈的节律，但没有仓鼠对LD循环表现出同步化。有能力的昼夜振荡器显然存在于SCN之外，至少距离0.5毫米或更远，并且至少有一些是可被非光信号同步化的。损伤较大的动物中较弱的同步化表明，可被非光信号同步化的振荡器也存在于SCN内或其紧邻区域。
