不同光暗循环下小鼠自发活动生物节律周期的频率分析

Frequency Analysis of Periods of Spontaneous Biological Rhythm in Mice under Different Light-dark Cycle

目的探讨不同光-暗循环条件下小鼠的自发性活动是否存在3.5d节律、7d节律以及10d节律。方法以小鼠为动物模型,排除社会活动因素对生物节律的影响,采用红外线检测系统检测小鼠自发性活动,对不同光-暗循环作用下小鼠自发活动的多频率生物节律进行了研究。结果用余弦法的频谱分析发现:在10h光照(L)/10h黑暗(D)环境下,小鼠的自发活动存在明显的τ=20h的近日节律和τ=10h的近半日节律(P<0.001),以及较弱的近7d节律和近3.5d节律,P<0.01;在12h(L)/12h(D)环境下,存在很强的24h为周期的近日节律和12h为周期的近半日节律,P<0.001,未见近7d节律存在;在14h(L)/14h(D)环境下,以τ=28h为周期的近日节律和τ=14h的近半日节律表现明显(P<0.001),同时亦有较弱的近7d节律。上述情况下,小鼠均未发现10日节律。结论生物体存在多种频率的生物节律,其节律的特征受到光-暗循环的影响。

Objective To make clear whether circaseptan and circasemiseptan rhythms exist as endogenous rhythms, and to investigate whether organisms have a 10 d rhythm. Method Mice were used as the animal model. Multi-frequency biological rhythm of mice locomotor activity under the different light （L）-dark （D） cycle conditions were analyzed. Result The results showed that under 10 h（L）/10 h（D） cycle, mice （n =6） had an overt circadian （τ =20 h） and circasemidian （τ = 10 h） rhythms（P 〈 0.001 ）, and a slight circaseptan and circasemiseptan rhythm with periods; under 12 h（ L）/12 h（D） cycle, circadian （τ =24 h） and circasemidian （τ= 12 h） rhythm were observed definitely in mice （P 〈 0. 001 ）, however, circaseptan and circasemiseptan rhythm were not found. When living under 14 h（ L）/14 h（D） cycle, mice presented circadian （τ=28 h） and circasemidian （τ= 14 h） rhythms obviously （P 〈 0. 001 ）, but circaseptan and circasemiseptan rhythms were not obvious. Anyhow, no 10 d rhythm was found in the mice living under any different L-D cycle. Conclusion Multi-frequency biological rhythms do exist in mice and they are affected by different L-D cycle.