Dulloo A G, Seydoux J, Girardier L
Department of Physiology, University of Geneva, Switzerland.
Am J Physiol. 1990 Nov;259(5 Pt 1):E658-64. doi: 10.1152/ajpendo.1990.259.5.E658.
We examined the importance of corticosterone in elevated efficiency of energy utilization during refeeding after low food consumption. Energy balance studies during refeeding (over periods of 14 or 16 days) were conducted in rats previously food restricted for 16 days at 50% of normal food intake. Comparisons made with nonrestricted weight-matched controls after validation studies indicated that 2-wk-younger weight-matched controls had similar maintenance energy requirements and similar efficiency of energy utilization above maintenance (i.e., net efficiency) to nonrestricted age-matched controls. Results indicate that relative to controls refeeding after low food consumption was associated with enhanced energy conservation underlain by a 16-18% reduction (P less than 0.001) in total energy expenditure over a 14-day period. This metabolic adaptation for energy conservation resulted in a threefold increase (P less than 0.001) in body fat accretion but no difference in body protein deposition. Bilateral adrenalectomy (ADX) 2 days before refeeding reduced differences in energy expenditure between refed group and controls from 18 to 8% (P less than 0.01) and attenuated body fat gain from a three- to twofold increase (P less than 0.001) above control group. Effects of ADX were prevented by daily corticosterone replacement. Data suggest that after a period of low calorie intake an adaptive neurohormonal switching mechanism facilitates replenishment of fat stores during refeeding. This metabolic reorientation (characterized by an adaptive fall in energy expenditure) has both an adrenal as well as a nonadrenal component, because it is partially reversed by prior bilateral ADX, an effect attributed to removal of corticosterone-induced inhibition of thermogenesis.
我们研究了皮质酮在低食量后再喂食期间能量利用效率提高中的重要性。对先前16天按正常食物摄入量的50%进行食物限制的大鼠，在再喂食期间（14天或16天）进行了能量平衡研究。验证研究后与非限制体重匹配对照进行比较表明，年轻2周的体重匹配对照与非限制年龄匹配对照相比，具有相似的维持能量需求以及高于维持水平的相似能量利用效率（即净效率）。结果表明，相对于对照组，低食量后再喂食与能量节约增强有关，在14天期间总能量消耗减少16 - 18%（P < 0.001）。这种能量节约的代谢适应导致体脂积累增加了三倍（P < 0.001），但体蛋白沉积没有差异。再喂食前2天进行双侧肾上腺切除术（ADX），使再喂食组与对照组之间的能量消耗差异从18%降至8%（P < 0.01），并使体脂增加从高于对照组的三倍增加减弱至两倍增加（P < 0.001）。每日补充皮质酮可防止ADX的影响。数据表明，在一段时间低热量摄入后，一种适应性神经激素转换机制有助于在再喂食期间补充脂肪储备。这种代谢重新定向（以能量消耗适应性下降为特征）既有肾上腺成分也有非肾上腺成分，因为它被先前的双侧ADX部分逆转，这种作用归因于去除皮质酮诱导的产热抑制。
