摘要
在4℃急性冷暴露(1h,4h,8h,24h)和持续冷暴露(7d,14d,28d)条件下,测定中缅树鼩膈肌、心肌和肝脏的线粒体状态Ⅲ呼吸、状态Ⅳ呼吸、呼吸控制率(RCR)、线粒体蛋白含量以及肝脏线粒体P/O值的变化。结果表明:肝脏线粒体状态Ⅲ、状态Ⅳ呼吸随着低温处理时间的延长,呼吸速率均极显著增加,在28d后分别增加了132.9%、124.4%(P<0.01),RCR与对照比较,在8h和7d组分别显著增加了35.8%和48.4%(P<0.05),线粒体蛋白含量也极显著增加,在28d后增加了104.7%(P<0.01),P/O值在整个低温处理过程中呈下降趋势,在28d后降低了40.2%,达到极显著水平(P<0.01);膈肌线粒体状态Ⅲ呼吸在整个低温处理期间没有显著变化,状态Ⅳ呼吸在28d达到极显著增加(P<0.01,64.9%),RCR在28d后显著降低(P<0.05,42.1%),线粒体蛋白只有4h组有极显著增加(P<0.01,45.2%);心肌的状态Ⅲ呼吸在8h组有着极显著的增加(P<0.01,54.7%),状态Ⅳ呼吸随着低温处理时间的增加而显著增加,28d后增加了94.7%(P<0.01),RCR在28d后降低37.8%(P<0.01),线粒体蛋白表现出先下降再上升的趋势,8h组下降37.8%(P<0.01),28d增加25.2%(P<0.05)。说明中缅树鼩在冷胁迫的条件下肝脏线粒体呼吸能力显著增强,主要表现为状态Ⅳ呼吸即质子漏产热的显著增强,膈肌和心肌的线粒体呼吸也具有一定的适应性变化,补偿了冷胁迫条件下中缅树鼩增加的能量需求,是中缅树鼩在冷胁迫中重要的适应对策。
The state Ⅲ respiratory ability, state Ⅳ respiratory ability, respiration control ratio （RCR） , total protein content and mitochondrial protein contents of liver, diaphragm and cardiac muscle in tree shrews （ Tupaia belangeri） were measured during acutecy cold exposure for 1 h, 4 hs, 8 hs, 24 hs, and prolonged cold exposure for7 days, 21 days and 28 days. The state Ⅲ respiratory ability, state Ⅳ respiratory ability were measured by oxygen electrodes and the total protein content and mitochondrial protein contents were measured by Lowry method. The liver mitochondrial state Ⅲ and Ⅳ respiratory ability both greatly increased with prolonged cold exposure, 132.9% and 124.4% （ P 〈 0. 01 ） respectively increased after 28 d. Compared to the controls, RCR increased by 35.8% and 48.4% （P 〈 0. 05） in the 8 h and 7 d groups and the content of mitochondrial protein also increased by 104. 66% （P 〈0. 01 ） while the P/O value showed a decreasing trend during the whole cold exposure process, showing a very significant level after 28 d, decreasing by 40.2% （ P 〈 0. 01 ）. The respiration of the diaphragm muscle mitochondrial state Ⅲ did not change evidently during the cold exposure process, however, the state Ⅳ respiration increased by 54. 7% （P 〈0. 01 ） while RCR decreased by 42. 1% （P 〈 0.05 ） and the mitochondrial protein increased by 45.2% （ P 〈0. 01）. only in the 4 h group. The state Ⅲ respiration of the cardiac muscle mitochondria increased by 54. 7% （P 〈0. 01 ） in the8 h group and the state Ⅳ respiration significantly increased 94. 7% by the cold exposure （P 〈0.01 ） , while RCR decreased by 37.8% （P 〈0. 01 ） and the content of mitochondrial protein showed a trend that increased at first and decreased later and the 8 h group decreased by 37.8% （P 〈0. 01 ）, and increased by 25.2% （P 〈 0. 05 ） after 28 d. The mitochondrial respiration of liver was significantly enhanced during the cold stress incorporating that the increase of proton leakage and there was some adaptive change in the mitochondria respiration of diaphragm muscle and cardiac muscle also, which compensated for the increasing energy requirements to some degree under the cold condition. These were important strategies for tupaia belanzeri to adapt to the cold.
出处
《兽类学报》
CAS
CSCD
北大核心
2008年第2期157-164,共8页
Acta Theriologica Sinica
基金
国家自然科学基金资助项目(30260021,30560026)
云南省重点应用项目
关键词
低温
中缅树鼩
膈肌
心肌
肝脏
线粒体呼吸
质子漏
Cold exposure
Liver
Muscle
Mitochondrial respiration
Tupaia belangeri
Proton leak
