van Jaarsveld Barry, Bennett Nigel C, Hart Daniel W, Oosthuizen Maria K
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa.
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa.
J Therm Biol. 2019 Jan;79:24-32. doi: 10.1016/j.jtherbio.2018.11.013. Epub 2018 Nov 26.
African mole-rats (family: Bathyergidae) are strictly subterranean mammals that reside in extensive networks of underground tunnels. They are rarely, if ever, exposed to light and experience muted temperature ranges. Despite these constant conditions, the presence of a functional circadian clock capable of entraining to external light cues has been reported for a number of species. In this study, we examine a social mole-rat species, Cryptomys hottentotus mahali, to determine if it possesses a functional circadian clock that is capable of perceiving light and ambient temperature cycles, and can integrate these cues into circadian rhythms of locomotor activity and core body temperature. Eight male and eight female, non-reproductive individuals were subjected to six cycles of varying light and temperature regimes. The majority of the individuals displayed daily rhythms of locomotor activity and body temperature that are synchronised to the external light and temperature cycles. Furthermore, endogenous rhythms of both locomotor activity and core body temperature were displayed under constant conditions. Thus, we can conclude that C. h. mahali possesses a functional circadian clock that can integrate external light and temperature cues into circadian rhythms of locomotor activity and core-body temperature.
非洲鼹形鼠（家族：滨鼠科）是严格穴居的哺乳动物，栖息在广泛的地下隧道网络中。它们极少暴露在光线下，经历的温度范围也较为温和。尽管环境条件恒定，但已有报道称多种非洲鼹形鼠具有能够根据外部光照线索进行同步的功能性昼夜节律钟。在本研究中，我们对一种群居鼹形鼠——马哈利隐鼠进行了研究，以确定它是否拥有一个能够感知光照和环境温度周期，并能将这些线索整合到运动活动和核心体温的昼夜节律中的功能性昼夜节律钟。八只雄性和八只雌性未繁殖个体经历了六个不同光照和温度条件的周期。大多数个体表现出与外部光照和温度周期同步的每日运动活动和体温节律。此外，在恒定条件下也表现出运动活动和核心体温的内源性节律。因此，我们可以得出结论，马哈利隐鼠拥有一个功能性昼夜节律钟，能够将外部光照和温度线索整合到运动活动和核心体温的昼夜节律中。
