中文摘要：

育肥完成后到冬眠前的阶段被认为是贮脂类冬眠动物从体温常态到冬眠之间的过渡阶段。为研究此阶段瘦素对能量平衡和体温调节的作用,将完成育肥的达乌尔黄鼠随机分成3组,分别在侧脑室植入微渗透泵,持续灌注瘦素（0.5μg/day）、瘦素拮抗剂（0.5μg/day瘦素＋5μg/day瘦素拮抗剂）以及人工脑脊液（对照组）,为期4周。为了检测瘦素对动物入眠的影响,我们在药物处理最后一周将动物移入低温（5℃±1℃）、恒黑条件下诱导蛰眠。药物处理过程中测定动物体重、能量摄入、代谢率和体温,药物处理结束后测定身体脂肪重量、褐色脂肪组织中解偶联蛋白1（UCP1）含量以及血清中与能量平衡相关的激素水平。结果发现：育肥后达乌尔黄鼠能量摄入、体重和每日体温自发降低。低温条件下,对照组中50%个体自发进入冬眠状态。瘦素处理和瘦素拮抗剂处理对能量摄入和体重变化没有显著影响。瘦素处理对入眠率没有影响,瘦素拮抗剂处理减少蛰眠表达。瘦素拮抗剂组血清中T4水平高于瘦素处理组。育肥后期瘦素以及瘦素拮抗剂处理对脂肪重量、代谢率以及UCP1含量没有显著影响。结果表明,瘦素对育肥结束后达乌尔黄鼠的冬眠表达具有一定调节作用。

英文摘要：

Post-fattening period is regarded as the transitive period from euthermia to hibernation in fat-storing hibernators,within which hibernators are characterized by gradually decreased food intake,body mass and body temperature（Tb）. This study sought to test the effects of leptin on energy balance and thermoregulation in post-fattening Daurian ground squirrel（Spermophilus dauricus）,a typical fat-storing hibernator. The animals were treated with leptin（0. 5 μg/day）,leptin antagonist（0. 5 μg / day leptin ＋ 5 μg / day leptin antagonist） or artificial cerebrospinal fluid（control group） through intracerebroventricular injection for 4 weeks. The last week of administration was coupled with cold exposure（5℃ ± 1℃） in constant darkness for facilitating torpor. Body mass,energy intake,resting metabolic rate（RMR） and Tbwere measured throughout the experiment. The mass of white adipose tissue（WAT）,uncoupling protein 1（UCP1） content in brown adipose tissue and the concentration of energetics-related hormones in serum were measured at the end of drug administration.The results showed that food intake,body mass and Tbspontaneously decreased after fattening. In the control group,50%animals fell into the torpid state after cold exposure. Leptin administration had no effect on ratio of animal entering torpor.However,the hibernation expression decreased and T4 concentration increased in the leptin antagonist group were significantly higher than those in the leptin-administrated group. Leptin and leptin antagonist administrations decreased WAT mass by about 25% compared with that in the control group. There were no significant effects of leptin and leptin antagonist administration on energy budget and UCP1 content. Our results suggest that leptin has limited roles on energy regulation butcan affect the torpor patterns in the post-fattening Daurian ground squirrels.