关键词: 非颤抖性产热, 褐色脂肪组织, 高原鼠兔, 根田鼠, 热能调节, 去甲肾上腺素, 生存对策。

Abstract: This work Was carried out at Haibcei Alpine Meadow Ecosystem Research Station of Menyuan．Qinghai Province，with an altitude of about 3200 meters (Lat．37°29′-37°45′N ，Long．101°12′ - 101°33′)，from May 1987 to April 1988．Plateau pika (Ochotona curzoniae )androot vole (Microtus oecottomus)were live-trapped everymonth in the Kobresia humilis meadow and potenlilla fruticosa shrub respectively．The norepinephrine stimulated nonshivering thermogenesis(NE—NST)were both measured at 25℃ and l5℃ ．The seasonal variations in NST capacity and the relationship between NST and brown adipose tissue (BAT) were analyzed in both species，and the adaptive survival strategies for those living in a cold and high altitude environment were discussed also The main results obtained are as follows：
1.The NE-NST was expressed in three forms：the maximum metabolic response to NE (NST_max )，the absolute increase in Oxygen consumption (NST_max -RMR)，and the percentage of RMR ( %RMR)．The seasonal change patterns of the three forms are both simi1ar at 25℃ and l5℃ in M ．Oeconomus．The lowest value occurred in summer(25℃，NST_max ：19.0mlO₂／g^0.73 h，NST_max -RMR：7.2mlO₂／g^0.73 h，%RMR：64% and 15℃，19.2mlO²/g^0.73. h， 4.5mlO₂／g^0.73 · h，31% respectively)，and the highest in winter (January) (25℃，27．0mlO₂／g^0.73.h，17．9mlO 2／g^0.73·h，216%, and 15℃，28.5mlO₂／g^0.73 ·
h．14.2 mlC ₂／g^0.73 h，111%，respectively)．NST_maxmaintained high level all year in 0．curzoniae at 25℃，but showed a significant ircrease in December at 15℃．However，when NST expressed in other two farms the seasonal change patterns are similar to that 0f M .Oeconomus at both 25℃ and 15℃． The lowest value was seen in August(25℃ ，3.7mlO ₂／g^0.73.h，47%; and 15℃，2.6mlO ₂／g^0.73.h，26%，respectively)，and reach the peak in December (25℃， 6.2miO ₂／g^0.73·h．125% ; and 15℃，5.8m10₂／g^0.73·h，67％，respectively)． The seasonal variations of NST are inversely related tothemouthly average air temperatures in both species at 25℃ and 15℃ ．
2．There is a significant direct relatienship between NST and EAT
． During the reduced food availability and increased cold winter。with the increasingin relative weight of BAT，mitochondria size of BATcell and cristae numbers of mitochondria ，the capacity of NE-NST increased also in both O．curzoniae and M .ceconomus
3．A general adaptive strategies to winter for nonhibernating small mammals at Haibei Alpine Meadow Ecosystem incorporate many behavioral，physiological and morpho-anatomical adaptations including：huddling for reduced heat 1oss，decreased activity-and body weight during periods of cold，increased thermogenic capacity due to NST with resultant hypertrophy of BAT and minimized thermal conductance by increasing hair density and length in winter，and so on．Animalcan utilize a variety of combinations of these factors in adjusting to cold season．

Key words: Nonshlvering thermogenesis, NST, Brown adipose tissue, BAT, Ochotona curzoniae, Microtus oeconomus, Thermoregulation, Norepinephrine, NE, Survival strategy.