Abstract: The oriental voles (Eothenomys miletus)is a typical species inhabiting Hengduan mountains region of Yunnan Province. In our paper，we interested in the characteristics of thermoregulation, including the feathers of heat production at individual level, the biochemical mechanisms in liver and brown adipose tissue (BAT).The body temperature (T_b) at room temperature(16.0-24.8℃) was 35.9±0.37℃(N=99), Its T_b was on1y stable in 15-30℃ approximately. When the ambient temperature reached 32.5℃, the animals were hyperthermal obviously. The thermal neutral zone (TNZ) was from 25℃ to30℃, and the minimum resting metabolic rate (BMR) was 2.71±0.18 ml O₂/ g. h, which was 213. 2±10.3% of previous predicted body mass. At the ambient temperature below 27.5℃, there was a negative relationship between RMR and T_a，which was be described: RMR= 6.473–0.145 T_a ( T_a : 5-27. 5℃;r=-0.848, P<0.001;N = 74). The average minimum thermal conductance(Cm)was 0.23士0.01 ml O₂/ g. h. ℃,which was 141.7±0.6% of previous predicted by body mass. When the T_a was below 30℃, Cm increased slowly with T_a increasing, and the relationship of Cm and T_a was as follows: Cm =0. 1219±0.0078T_a (T_a: 5-27.5℃;r=–0.7216;P < 0. 0001，N = 74). When T_a was above 30℃, Cm increased strikingly. The consumption of oxygen induced by noradrenaline(NE) injected was 5.18±0.01 ml O₂/ g. h (N=11;T_a=25 ℃.The liver mass was 2.11±0.25 g, Liver/ BW×100% was 5.3%(N=11), the total and mitochondrial protein content were 76±3.8 and 20. 5±1.9 mg/g, respectively. The activity of cytochrome C oxidase(COX) in mitochondria was 88.5±8.4 (ng O atom/ mg mit. protein min).The BAT mass was 0.33±0.05 g BAT/BW×100% was 0.84%(N=11)，the total and mitochondrial protein content were 31.5士1.4 and 18.8±0.05 mg/g respectively; The activity of cytochrome C oxidase(COX) in mitochondria was 1731.6±146 (ng O atom/ mg mit. protein min).The mitochondrial respirations of state Ⅳ was 76.43±1.6(ng O atom/ mg mit. protein min).In conclusion that the high level of RMR and NSTmax in the voles were related with adapting to altitude environments; the thermogenical capacity of liver was the main factor resulting in its RMR increasing.

Key words: Oriental vole (Eothenomys miletus), Thermogenesis, RMR, NSTmax

摘要： 大绒鼠为横断山脉地区小型哺乳动物的典型代表; 其体温仅能在15～30℃范围内维持稳定; 在热中性区内, 最低静止代谢率为2.71±0.13 ml O₂/g.h, 为其体重预期值的203.2±10.13%; F-值 {(RMR/Me)/(Cm/ C'} 为0.99±0.05; 在 25℃的NSTmax为 5.18±0.19)ml O₂/g.h; BAT 重量为0.33±0.05 g, 为体重的0.84%, BAT细胞线粒体的产热活性较高;肝脏也具有较强的产热活性。大绒鼠的产热特征和体温调节模式很可能反映了横断山地区小型啮齿动物的特征。

关键词: 大绒鼠, 产热, 体温调节