Effects of rearing temperature on sympathoadrenal activity in young adult rats.
Effects of rearing temperature on sympathoadrenal activity in young adult rats.
复制标题
饲养温度对年轻成年大鼠交感肾上腺活性的影响。
DOI：
10.1152/ajpregu.00525.2001
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Boufath,Nadine
中科院分区：
文献类型：
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作者：
Young,JamesB;Weiss,Jeffrey;Boufath,Nadine
在18°C下饲养的动物表现出棕色脂肪组织（BAT）的神经支配增强，成年后的耐寒性更强，但与30°C下饲养的大鼠相比，喂食强化饮食时体重增加更多。为了探索这一矛盾，在18或30°C下饲养至2月龄的雄性和雌性大鼠中，使用[3 H]去甲肾上腺素（[3 H]NE）周转和尿儿茶酚胺排泄技术检查了交感肾上腺活性。BAT中的基因表达也分析了几个交感神经相关蛋白。虽然心脏中的[3 H]NE周转在组间没有差异，但BAT中的[3 H]NE周转在18° C饲养的动物中持续升高，甚至在从凉爽环境中取出后2个月也是如此。解偶联蛋白1和3、GLUT-4、瘦素和α 1A-肾上腺素能受体的基因表达在BAT中更丰富，并且在18° C饲养的动物中禁食抑制肾上腺素排泄的增加。这些研究表明，尽管对BAT的交感神经输入紧张性升高，但在早期生活中暴露于18°C导致的肥胖发生。肾上腺素对禁食的反应性降低可能起作用。
Animals reared at 18°C exhibit enhanced innervation of brown adipose tissue (BAT) and greater cold tolerance as adults, yet gain more weight when fed an enriched diet compared with rats reared at 30°C. To explore this paradox, sympathoadrenal activity was examined using techniques of [3H]norepinephrine ([3H]NE) turnover and urinary catecholamine excretion in male and female rats reared until 2 mo of age at 18 or 30°C. Gene expression in BAT was also analyzed for several sympathetically related proteins. Although [3H]NE turnover in heart did not differ between groups, [3H]NE turnover in BAT was consistently elevated in the 18°C-reared animals, even 2 mo after removal from the cool environment. Gene expression for uncoupling proteins 1 and 3, GLUT-4, leptin, and the α1A-adrenergic receptor was more abundant in BAT and the increase in epinephrine excretion with fasting suppressed in 18°C-reared animals. These studies demonstrate that obesity consequent to exposure to 18°C in early life occurs despite tonic elevation of sympathetic input to BAT. Diminished adrenal epinephrine responsiveness to fasting may play a contributory role.