冷驯化对大绒鼠褐色脂肪组织产热活性的影响

Effect of Cold Exposure on Thermogenic Capacity of Brown Adipose Tissue in EothenomysMiletus

大绒鼠(Eothenomys miletus)为横断山区的固有种.在冷驯化((5±0.5)℃;光照:12L∶12D)过程中,大绒鼠体重降低,非颤抖性产热(Non-shivering thermogensis,NST)随冷驯化时间延长而显著增加;与NST增加相应,褐色脂肪组织(Brown adipose tissue,BAT)的总蛋白质含量(Total protein,TP)和线粒体蛋白含量(Mitochondrial protein,MP)、细胞色素C氧化酶活性、线粒体状态IV呼吸能力和$-磷酸甘油氧化酶活性与对照组比较均出现了显著增加.这些变化是大绒鼠在低温下产热增加的细胞学基础.但是,不论是NST、还是细胞水平的变化强度,均没有典型的北方种类强烈,表现出对横断山区特殊的产热适应特征,很可能代表了横断山区小型哺乳动物在冷适应条件下的产热模式.

Eothenomys miletus is an endemic species distributed in Hengduan mountain region. E. miletus decreased body mass under cold acclimation （ （5 ± 0. 5） ℃ ; light ： 12L：12 D）, non-shive- ring thermogenosis（NST） increased significantly during the time of cold acclimation;according to the increase of NST,total protein content and mitochondrial protein contents, mitochondrial respiratory state IV,cytochrome c oxidase and α- glycerophosphate oxidase activity increased significantly of brown adipose tissue（BAT）. These changes were the cytological basis of the increase of thermogenosis under low temperature in E. miletus. However, changes in the strength of the NST,or the cell level, were not strongly compared with the typical of the northern species, showed the special features of regulation of heat production, may reflect the thermoregulation mode and characteristics of small mammals in Hengduan mountain region.