Mrosovsky N, Foster R G, Salmon P A
Department of Zoology, University of Toronto, Ontario, Canada.
J Comp Physiol A. 1999 Apr;184(4):423-8. doi: 10.1007/s003590050341.
Mutant mice with retinal degeneration (rd/rd) were given 1-h pulses of light of varying brightness at times of the night when they would normally be active. The mutant mice showed a significantly greater inhibition of locomotor activity to light (negative masking) than wildtype controls. Lack of impairment, or even enhancement of negative masking suggests that this response may depend on sparing in retinally degenerate mice of the same receptor type that mediates clock resetting, because synchronization of the circadian system is known to be unimpaired in these mutants. With very dim light pulses, mutants did not change their activity, but wildtypes actually became more active (positive masking). Positive and negative masking appear to depend on different sensory and central processes.
在夜间正常活跃时段，给患有视网膜变性（rd/rd）的突变小鼠施加不同亮度的1小时光脉冲。与野生型对照相比，突变小鼠对光的运动活动抑制（负性掩盖）明显更强。负性掩盖缺乏损伤甚至增强表明，这种反应可能取决于视网膜变性小鼠中介导生物钟重置的相同受体类型的保留，因为已知这些突变体的昼夜节律系统同步未受损。在非常昏暗的光脉冲下，突变体没有改变其活动，但野生型实际上变得更加活跃（正性掩盖）。正性和负性掩盖似乎取决于不同的感觉和中枢过程。
