BROWN ADIPOSE TISSUE + RESPONSE OF NEW-BORN RABBITS TO COLD
BROWN ADIPOSE TISSUE + RESPONSE OF NEW-BORN RABBITS TO COLD
复制标题
DOI：
10.1113/jphysiol.1964.sp007414
复制
发表时间：
1964-01-01
影响因子：
5.5
通讯作者：
HULL, D
中科院分区：
文献类型：
--
作者：
DAWKINS, MJR;HULL, D
肩胛骨之间和颈部周围的棕色脂肪组织占新生兔子体重的5%。接触颜色或静脉输注去甲肾上腺素会增加新生兔的耗氧量，并伴有棕色脂肪组织局部产热。暴露于寒冷时棕色脂肪组织的局部产热被缺氧所消除。普萘洛尔消除了输注去甲肾上腺素期间的局部产热。暴露于寒冷或输注去甲肾上腺素会导致血浆游离脂肪酸小幅上升，但血浆甘油大幅上升。冷暴露期间脂肪组织的游离脂肪酸水平表明，水解释放的大部分游离脂肪酸在棕色脂肪组织内代谢。对肩胛间脂肪组织的体外研究表明，新生儿的脂肪分解速率是成人的3倍，但游离脂肪酸的释放速率是成人的1/2。棕色脂肪组织中不存在甘油激酶活性，但新生兔的肝脏中存在甘油激酶活性。棕色脂肪组织在切片和匀浆中具有异常高的体外耗氧量。这些观察结果间接表明，棕色脂肪组织对新生兔对寒冷和去甲肾上腺素的代谢反应做出了重大贡献。
Brown adipose tissue between the scapulae and around the neck represents 5% of the body weight of newborn rabbits. Exposure to color or intravenous infusion of noradrenaline increased the oxygen consumption of newborn rabbits and was accompanied by local heat production in brown adipose tissue. Local heat production in brown adipose tissue during exposure to cold was abolished by hypoxia. Local heat production during infusion of noradrenaline was abolished by pronethalol. Exposure to cold or infusion of noradrenaline caused a small rise in plasma free fatty acids but a large rise in plasma glycerol. Adipose tissue levels of free fatty acids during cold exposure indicated that most of the free fatty acids liberated by hyrolysis were metabolished within brown adipose tissue. In vitro studies of inter-scapular adipose tissue showed that the rate of lipolysis was 3 times greater in the newborn than in the adult, but the rate of release of free fatty acids was 1/2 that of the adult. Glycerol kinase activity was absent from brown adipose tissue but was present in the liver of newborn rabbits. Brown adipose tissue had exceptionality high in vitro oxygen consumption, in slices and homogenates. These observations indirectly suggest that brown adipose tissue makes a significant contribution to the metabolic response of newborn rabbits to cold and noradrenaline.