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长爪沙鼠季节性产热特征比较 总被引:3,自引:3,他引:0
与夏季相比、冬季长爪沙鼠的静止代谢率和非颤抖性产热显著升高;褐色脂肪组织线粒体的细胞色素C氧化酶与α-磷酸甘油氧化酶活力升高,组织总蛋白质及线粒体蛋白质含量增加,而组织的脂肪含量减少;血清T3含量和T3/T4值都显著增加。但是肝脏的各项产热指标变化不显著、表明褐色脂肪组织的产热功能具有季节波动性,是长爪沙鼠适应性产热的主要来源器官. 相似文献
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达乌尔黄鼠产热的季节性变化 总被引:4,自引:2,他引:4
达乌尔黄鼠(Citellusdauricus)的产热表现出明显的季节性变化。在非冬眠期,静止代谢率(RMR)和非颤抖性产热(NST)于春季最高,秋季次之,夏季最低。冬眠期,RMR降到极低水平,只为春季的3.0%。肝脏的线粒体蛋白含量、线粒体呼吸和细胞色素C氧化酶活力在秋季显著高于其它各季。褐色脂肪组织(BAT)的重量、线粒体蛋白含量、细胞色素C氧化酶活力和α-磷酸甘油氧化酶活力,在夏季处于一年中的最低水平,到了冬季这些指标达到一年中的最高水平。在非冬眠季节BAT产热能力升高时,NST能力也相应升高,这表明BAT产热能力的增强是NST能力提高的部分机制。达乌尔黄鼠血清T_4含量在年周期中没有明显改变,冬眠时血清T_3含量显著高于其它各季。 相似文献
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中缅树鼩的非颤抖性产热及细胞呼吸特征 总被引:6,自引:0,他引:6
中缅树鼩(Tupaia belangeri chinensis)是东南亚树鼩中分布最北的一个种。在热中性区内的非颤抖性产热(nonshivering thermogenesis NST)分别为2.57±0.21(冬)和2.21±0.12(夏)mlO_2/(g·h);分别为体重预期值的75.9%和61.2%,两者不仅冬季显著高于夏季,而且亦高于典型的热带种类,但低于温带类群。褐色脂肪组织(brown adipose tissue,BAT)的重量冬季为0.622±0.015 S,夏季0.532±0.80 g,冬季也显著高于夏季;同时,BAT总蛋白含量、线粒体蛋白含量以及细胞α-磷酸甘油氧化酶和细胞色素C氧化酶活性,冬季也显著高于夏季,但增加的比例较温带种类低;而肝脏细胞的上述指标及线粒体状态Ⅲ、状态Ⅳ呼吸等,冬夏两季均无显著差异。因此,中缅树鼩的NST和细胞产热能力介于热带与温带类群之间,显示出向温带类型过渡的趋势。 相似文献
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非冬眠期达乌尔黄鼠对低温的适应性产热 总被引:1,自引:1,他引:0
达乌尔黄鼠在夏季冷驯化低温环境下(5±1℃)暴露4周后,导致脂肪积累的抑制;其静止代谢率(RMR)和非颤抖性产热(NST)分别提高了12%和85%;肝脏线粒体的蛋白含量、状态3呼吸和细胞色素C氧化酶活力分别提高了22%、42%和48%,表明在低温环境下肝脏线粒体产热能力的增强是RMR提高的细胞学机制之一;褐色脂肪组织(BAT)的重量、蛋白含量、细胞色素C氧化酶活力和α-磷酸甘油氧化酶活力极显著提高,表明在低温环境下BAT是达乌尔黄鼠的主要产热器官,BAT产热能力的增强是NST提高的重要细胞学机制之一。冷驯化没有引起达乌尔黄鼠血清T3、T4含量的变化 相似文献
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中缅树Qu的非颤抖性产热及细胞呼吸特征 总被引:4,自引:0,他引:4
中缅树qu(Tupaia belangeri chinensis)是东南亚树qu中分布最北的一个种。在热中性区内的非颤抖性产热(nonshivering thermogenesis NST)分别为2.57±0.21(冬)和2.21±0.12(夏)mlO[2]/(g·h);分别为体重预期值的75.9%和61.2%,两者不仅冬季显著高于夏季,而且亦高于典型的热带种类,但低于温带类群。褐色脂肪组织(brown adipose tissue,BAT)的重量冬季为0.622±0.015 g,夏季0.532±0.80 g,冬季也显著高于夏季;同时,BAT总蛋白含量、线粒体蛋白含量以及细胞α-磷酸甘油氧化酶和细胞色素C氧化酶活性,冬季也显著高于夏季,但增加的比例较温带种类低;而肝脏细胞的上述指标及线粒体状态Ⅲ、状态Ⅳ呼吸等,冬夏两季均无显著差异。因此,中缅树qu的NST和细胞产热能力介于热带与温带类群之间,显示出向温带类型过渡的趋势。 相似文献
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树麻雀肝脏和肌肉产热特征的季节性变化 总被引:6,自引:0,他引:6
北温带的小型鸟类,通过增加产热来适应低温环境.基础代谢率(BMR)是内温动物能量预算的重要组成部分.本研究中我们分别在冬季和夏季测定了树麻雀(Passer montanus)的BMR、肝脏和肌肉的线粒体蛋白含量、线粒体呼吸及细胞色素C氧化酶(COX)活力及血清中甲状腺激素(T4)及甲状腺原氨酸(T3)含量的变化.结果显示:树麻雀的体重和BMR冬季显著高于夏季;肝脏的线粒体呼吸、肝脏和肌肉的COX活力冬季较高,夏季较低;血清T3浓度冬季明显高于夏季.这些结果表明:在野外条件下,肝脏和肌肉在细胞水平产热能力的提高和血清T3含量的增加,是树麻雀抵御冬季寒冷的重要方式之一. 相似文献
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Zhang ZQ Wang DH 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,148(2):346-353
Seasonal adjustments in body mass (BM), nonshivering thermogenesis (NST) and several physiological, hormonal, and biochemical markers were measured in wild-trapped Mongolian gerbils (Meriones unguiculatus) from Inner Mongolia, China. Sexual differences were detected in BM, NST, brown adipose tissue (BAT) mass, and mitochondrial protein content. BM and NST in males were higher in winter (January) and spring (May) than in summer (August), and BM of females was also the highest in winter, but NST remained relatively constant throughout the year. Cytochrome c oxidase activity and mitochondrial uncoupling protein 1 (UCP1) content in BAT were enhanced in winter in males or females, respectively. Serum leptin concentration was the lowest in winter and positively correlated with BM and body fat mass but was negatively correlated with BAT UCP1 content. These data suggest that wild Mongolian gerbils do not depend on a decrease in BM, but instead increase their thermogenic capacity to cope with cold stress. Leptin may be involved in the seasonal regulation in energy balance and thermogenesis in field Mongolian gerbils. 相似文献
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《Journal of thermal biology》2005,30(6):431-436
- (1)To investigate the changes of brown adipose tissue (BAT) thermogenic capacity in primiparous Brandt's voles during different phases of reproduction, BAT weight, mitochondrial protein concentration, cytochrome c oxidase (COX) activity, and uncoupling protein (UCP1) contents were measured.
- (2)Both cytochrome c oxidase activity and UCP1 contents decreased significantly during lactation, suggesting that thermogenic capacity was suppressed.
- (3)The decrease of thermogenic capacity during reproduction, especially during lactation, is compensation to the large demand of energy for reproduction. This is advantageous for energy conservation and lactation in Brandt's voles. UCP1 is the base of molecular thermogenesis of BAT in Brandt's voles.
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- To investigate the role of photoperiod on the regulation of energy budgets and thermogenesis in Mongolian gerbils, body mass (BM), body fat mass (BFM), basal metabolic rate (BMR), nonshivering thermogenesis (NST), gross energy intake (GEI), mitochondrial cytochrome c oxidase (COX) activity and uncoupling protein1 (UCP1) content of brown adipose tissue (BAT), and serum tri-iodothyronine (T3), thyroxine (T4) and leptin levels were measured. 相似文献
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J Houst?k J Kopecky M Baudysová D Janíková S Pavelka P Klement 《Biochimica et biophysica acta》1990,1018(2-3):243-247
Differentiation and biogenesis of mitochondria in brown adipose tissue (BAT) was studied in situ and in cell culture by Western blotting, enzyme activity measurements, [35S]methionine incorporation and immunofluorescence microscopy. In different rodent species the perinatal development of BAT thermogenic function resulted from the formation of thermogenic mitochondria which replaced the preexisting nonthermogenic mitochondria. Their biogenesis was characterized by the sudden appearance and rapid increase of the uncoupling protein (UCP), increase of cytochrome oxidase (COX) and decrease of H(+)-ATPase. In primary cell culture, differentiation of precursor cells from mouse BAT to typical multilocular adipocytes was accompanied by increasing content of COX and H(+)-ATPase. A selective synthesis of UCP was induced by activation of beta-adrenergic receptors or by elevated levels of cellular cAMP. UCP was quantitatively incorporated into mitochondria and within 24 h after stimulation reached near physiological concentration. Both in situ and in cell culture, the conditions enabling the expression of UCP gene were accompanied by activation of intracellular thyroxine 5'-deiodinase. 相似文献
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小型哺乳动物通过产热能力的调整来应对环境的胁迫。为探究外源瘦素对不同地区大绒鼠(Eothenomys miletus)适应性产热的影响,选取云南昆明和大理地区捕获的大绒鼠各14只,置于25℃±1℃,光周期为12L∶12D的环境中,每日腹腔注射瘦素,持续28 d。以LT502电子天平每两天测定大绒鼠的体重,采用食物平衡法每两天测定大绒鼠摄食量,以便携式呼吸代谢测量系统每7天测定静止代谢率(RMR)、非颤抖性产热(NST)。第28天处死动物后,采用酶联免疫吸附法测定线粒体蛋白含量、线粒体细胞色素c氧化酶(COX)活性、解偶联蛋白1(UCP1)含量、血清三碘甲状腺原氨酸(T3)、甲状腺素(T4)、瘦素水平以及促甲状腺激素释放激素(TRH)和促肾上腺皮质激素释放激素(CRH)水平。结果表明,注射瘦素后昆明和大理地区大绒鼠的体重和摄食量显著降低,RMR和NST增强,肝脏中线粒体蛋白含量和COX活性,褐色脂肪组织(BAT)中COX活性和UCP1含量,及血清T3、T4、T3/T4比值、TRH和CRH浓度均增加。瘦素水平与体重、摄食量呈负相关,血清T3水平与NST和UCP1含量呈正相关。此外,注射前昆... 相似文献
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Zheng WH Li M Liu JS Shao SL 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2008,151(4):519-525
Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. Changes in photoperiod, ambient temperature and food availability trigger seasonal acclimatization in physiology and behavior of many birds. In the present study, seasonal adjustments in several physiological, hormonal, and biochemical markers were examined in wild-captured Eurasian tree sparrows (Passer montanus) from the Heilongjiang Province in China. In winter sparrows had higher body mass and basal metabolic rate (BMR). Consistently, the dry mass of liver, heart, gizzard, small intestine, large intestine and total digestive tract were higher in winter than in that in summer. The contents of mitochondrial protein in liver, and state-4 respiration and cytochrome c oxidase (COX) activity in liver and muscle increased significantly in winter. Circulating level of serum triiodothyronine (T3) was significantly higher in winter than in summer. Together, these data suggest that tree sparrows mainly coped with cold by enhancing thermogenic capacities through increased organ masses and heightened activity of respiratory enzymes activities. The results support the view that prominent winter increases in BMR are manifestations of winter acclimatization in tree sparrows and that seasonal variation in metabolism in sparrows is similar to that in other small temperate-wintering birds. 相似文献
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Environmental factors play an important role in the seasonal adaptation of body mass and thermogenesis in small, wild mammals. The purpose of the present study was to test the hypothesis that ambient temperature was a cue to trigger the seasonal adjustments in body mass, energy intake, uncoupling protein 1 (UCP1) in brown adipose tissue (BAT), and other biochemical characteristics of Eothenomys miletus during 49 days of cold exposure. Our data demonstrated that cold acclimation induced a remarkable decrease in body mass, a significant increase in energy intake and metabolic rate, and high expression of UCP1 in BAT of E. miletus. Biochemical characteristics of BAT and liver respiration were also increased following cold acclimation. These data suggest that E. miletus reduced the body mass and increased energy intake and expenditure under cold acclimation. Increased expression of UCP1 was potentially involved in the regulation of energy metabolism and thermogenic capacity following cold acclimation. 相似文献
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Wang JM Zhang YM Wang DH 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2006,145(4):1703-553
The present study was designed to examine whether photoperiod alone was effective to induce seasonal regulations in physiology in root voles (Microtus oeconomus) from the Qinghai-Tibetan plateau noted for its extreme cold environment. Root voles were randomly assigned into either long photoperiod (LD; 16L:8D) or short photoperiod (SD; 8L:16D) for 4 weeks at constant temperature (20 degrees C). At the end of acclimation, SD voles showed lower body mass and body fat coupled with higher energy intake than LD voles. SD greatly enhanced thermogenic capacities in root voles, as indicated by elevated basal metabolic rate (BMR), nonshivering thermogenesis (NST), mitochondrial protein content and uncoupling protein-1 (UCP1) content in brown adipose tissue (BAT). Although no variations in serum leptin levels were found between SD and LD voles, serum leptin levels were positively correlated with body mass and body fat mass, and negatively correlated with energy intake and UCP1 content in BAT, respectively. To summarize, SD alone is effective in inducing higher thermogenic capacities and energy intake coupled with lower body mass and body fat mass in root voles. Leptin is potentially involved in the photoperiod induced body mass regulation and thermogenesis in root voles. 相似文献
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Environmental factors play an important role in the seasonal adaptation of body mass and thermogenesis in wild small mammals. In this study, we performed a factorial experiment (temperature x photoperiod) in which Brandt's voles and Mongolian gerbils were acclimated to different photoperiods (long photoperiod, 16L : 8D; short photoperiod, 8L : 16D) and temperatures (warm, 23 degrees C; cold, 5 degrees C) to test the hypothesis that photoperiod, temperature, or both together can trigger seasonal changes in serum leptin level, body mass, thermogenesis, and energy intake. Our data demonstrate that Brandt's voles showed a remarkable decrease in body mass in both the cold and a short photoperiod. However, no significant changes in body mass were found for gerbils exposed to similar conditions. The short photoperiod induced a decrease in serum leptin levels for both voles and gerbils that might contribute to an increase in energy intake. Furthermore, the short photoperiod induced an increase of uncoupling protein 1 (UCP1) content for both voles and gerbils, and cold can further enhance the increase in voles. No interactions between photoperiod and temperature were detected for the two species. Brandt's voles can decrease their body mass through changes in energy intake and expenditure, while Mongolian gerbils can keep body mass relatively stable by balancing energy metabolism under winterlike conditions. Leptin was potentially involved in the regulation of body mass and thermogenic capacity for the two species. 相似文献