Kavaliers M, Hirst M
Brain Res. 1983 Nov 21;279(1-2):387-93. doi: 10.1016/0006-8993(83)90216-0.
Daily rhythms in response to aversive thermal stimulation and the analgesic effectiveness of morphine were assessed by the hot-plate method with young (1-2 months), mature (8-12 months) and old (20-30 months) mice exposed to various light-dark conditions (LD 12:12; 16:8; 8:16 h). The patterns of response after saline or morphine varied with the specific light-dark conditions examined, but routinely, there were increases in response latency from the early portions of the light phase to later time, and a further enhancement of the time to respond with onset of the dark phase. The dark-phase response declined abruptly with the start of the light-phase. Significant age-related declines were observed in the elevated, dark-phase morphine-analgesic and basal aversive responses, with no consistent effects of age evident in the light-phase.
采用热板法，在不同光暗条件（12小时光照：12小时黑暗；16小时光照：8小时黑暗；8小时光照：16小时黑暗）下，对年轻（1 - 2个月）、成熟（8 - 12个月）和老年（20 - 30个月）小鼠进行测试，评估其对厌恶性热刺激的每日节律以及吗啡的镇痛效果。给予生理盐水或吗啡后的反应模式随所检测的特定光暗条件而变化，但通常情况下，从光照期早期到后期，反应潜伏期会增加，随着黑暗期开始，反应时间会进一步延长。黑暗期反应在光照期开始时会突然下降。在黑暗期吗啡镇痛和基础厌恶性反应增强方面，观察到了与年龄相关的显著下降，而在光照期未发现年龄的一致影响。
