中缅树鼩体温、代谢率和蒸发失水日节律

为研究中缅树鼩(Tupaia belangeri)体温、代谢率和蒸发失水的日节律变化,采用植入式体温计测定了中缅树鼩24 h的体温,以及24 h中4个时间段(05:00～07:00时、11:00～13:00时、17:00～19:00时和23:00～01:00时)热中性区(30℃)的静止代谢率(RMR)、非颤抖性产热(NST)和蒸发失水(EWL)。结果显示,中缅树鼩的体温具有日节律变化,最高值和最低值分别出现在11:00时和03:00时,各为(39.45±0.26)℃和(36.34±0.24)℃;静止代谢率、非颤抖性产热和蒸发失水在4个时间段都有显著差异,表现出显著的日节律变化,代谢率在23:00～01:00时最大,O2含量为(2.58±0.04)ml/(g.h),在11:00～13:00时最小,O2含量为(2.28±0.09)ml/(g.h);非颤抖性产热在05:00～07:00时最大,O2含量为(3.08±0.14)ml/(g.h),在11:00～13:00最小,O2含量为(2.69±0.63)ml/(g.h);蒸发失水在17:00～19:00时最大,失水量为(3.60±0.31)mg/(g.h)。结果表明,体温的日节律变化主要与环境温度的日节律变化和下午出窝取食活动性增强有关;当夜晚环境温度相对较低的时候,通过增强静止代谢率和非颤抖性产热来增加产热,而白天环境温度相对较高的时候,通过增强蒸发失水散热来调节体温。

Circadian Rhythms of Body Temperature, Metabolic Rates and Evaporative Water Loss in Tupaia belangeri

To study daily rhythms of body temperature,metabolic rates and evaporative water loss of Tupaia belangeri,we took measurements on body temperature(Tb) for 24 h by implanting thermometer into their body.We also measured rest metabolic rate(RMR),nonshivering thermogenesis(NST) and evaporative water loss(EWL) in 4 periods of 05:00-07:00,11:00-13:00,17:00-19:00 and 23:00-01:00 within 24 h.The body temperature showed a change in circadian rhythm with a maximum and minimum value of 39.45±0.26℃ and 36.34±0.24℃ at 11:00 and 03:00,respectively.The value of NST,RMR and EWL taken in the four periods within 24 h also significantly varied and exhibited a circadian rhythm.The minimum value of RMRTNZ was 2.28±0.09 ml/(g·h) at 11:00-13:00 and maximum value was 2.58±0.04 ml/(g·h) occurred at 23:00-01:00;the highest value of NST occurred at 05:00-07:00 valued at 3.08±0.14 ml/(g·h) and the lowest value was 2.69±0.06 ml/(g·h) exhibited at period of 11:00-13:00;The maximum value of EWL was taken at 17:00-19:00 with 3.60±0.31 mg/(g·h).The body temperature variation was varied with change of ambient temperature and with the activeness of the animal in the different period in the 24 h rhythm.The RMR and NST was increase in the night when the ambient temperature was decrease.The animal adjusted their body temperature by increasing EWL in the day.