Hypercortisolemia alters muscle protein anabolism following ingestion of essential amino acids
Hypercortisolemia alters muscle protein anabolism following ingestion of essential amino acids
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DOI：
10.1152/ajpendo.00397.2002
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发表时间：
2003-05-01
影响因子：
5.1
通讯作者：
Ferrando, AA
中科院分区：
文献类型：
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作者：
Paddon-Jones, D;Sheffield-Moore, M;Ferrando, AA
使人衰弱的损伤伴随着高皮质醇血症、肌肉萎缩和对食物的正常合成代谢反应的破坏。我们试图确定急性高皮质醇血症是否会改变肌肉蛋白质代谢后摄入一个强大的合成代谢刺激：必需氨基酸（EAA）。27小时（80 mug.kg（-1）.h（-1））的氢化可的松琥珀酸钠输注模拟了伴随严重损伤（>30 mug/dl）的皮质醇（C）水平（C + AA; n = 6）。对照组（AA）6例，静脉注射生理盐水。在摄入15 g EAA之前和之后，在预充（2.0 mumol/kg）恒定输注（0.05 mumol.kg（-1）.min（-1））L-[环-H-2（5）]苯丙氨酸期间获得股动静脉血样和肌肉活检。高皮质醇血症[36.5 +/- 2.1（C + AA）vs. 9.0 +/- 1.0 mug/dl（AA）]增加吸收后动脉、静脉和肌肉细胞内苯丙氨酸浓度。高皮质醇血症也增加了吸收后和EAA后的胰岛素浓度。净蛋白质平衡钝化（40%）EAA摄入后，但在C + AA组保持积极的一段更长的时间（60与180分钟）。因此，虽然蛋白质代谢的差异是明显的，EAA摄入改善肌肉蛋白质anterior在急性高皮质醇血症，并可能有助于减少肌肉损失后衰弱性损伤。
Debilitating injury is accompanied by hypercortisolemia, muscle wasting, and disruption of the normal anabolic response to food. We sought to determine whether acute hypercortisolemia alters muscle protein metabolism following ingestion of a potent anabolic stimulus: essential amino acids (EAA). A 27-h infusion (80 mug.kg(-1).h(-1)) of hydrocortisone sodium succinate mimicked cortisol ( C) levels accompanying severe injury (>30 mug/dl), (C + AA; n = 6). The control group ( AA) received intravenous saline (n = 6). Femoral arteriovenous blood samples and muscle biopsies were obtained during a primed ( 2.0 mumol/kg) constant infusion (0.05 mumol.kg(-1).min(-1)) of L-[ring-H-2(5)]phenylalanine before and after ingestion of 15 g of EAA. Hypercortisolemia [36.5 +/- 2.1 (C + AA) vs. 9.0 +/- 1.0 mug/dl (AA)] increased postabsorptive arterial, venous, and muscle intracellular phenylalanine concentrations. Hypercortisolemia also increased postabsorptive and post-EAA insulin concentrations. Net protein balance was blunted (40% lower) following EAA ingestion but remained positive for a greater period of time (60 vs. 180 min) in the C + AA group. Thus, although differences in protein metabolism were evident, EAA ingestion improved muscle protein anabolism during acute hypercortisolemia and may help minimize muscle loss following debilitating injury.