Coppack S W, Horowitz J F, Paramore D S, Cryer P E, Royal H D, Klein S
Department of Medicine, University College London Medical School, London N19 3UA, United Kingdom.
Am J Physiol. 1998 Nov;275(5):E830-4. doi: 10.1152/ajpendo.1998.275.5.E830.
We evaluated whole body and regional (subcutaneous abdominal adipose tissue and forearm) norepinephrine (NE) kinetics in seven lean (body mass index 21.3 +/- 0.5 kg/m2) and six upper body obese (body mass index 36.4 +/- 0.4 kg/m2) women who were matched on fat-free mass. NE kinetics were determined by infusing [3H]NE and obtaining blood samples from a radial artery, a deep forearm vein draining mostly skeletal muscle, and an abdominal vein draining subcutaneous abdominal fat. Mean systemic NE spillover tended to be higher in obese (2.82 +/- 0.49 nmol/min) than in lean (2.53 +/- 0.40 nmol/min) subjects, but the differences were not statistically significant. Adipose tissue and forearm NE spillover rates into plasma were greater in lean (0.91 +/- 0.08 pmol. 100 g tissue-1. min-1 and 1.01 +/- 0.09 pmol. 100 ml tissue-1. min-1, respectively) than in obese (0.26 +/- 0.05 pmol. 100 g tissue-1. min-1 and 0.58 +/- 0.11 pmol. 100 ml tissue-1. min-1, respectively) subjects (P < 0.01). These results demonstrate that adipose tissue is an active site for NE metabolism in humans. Adipose tissue NE spillover is considerably lower in obese than in lean women, which may contribute to the lower rate of lipolysis per kilogram of fat mass observed in obesity.
我们评估了7名体重正常（体重指数21.3±0.5kg/m²）和6名上身肥胖（体重指数36.4±0.4kg/m²）的女性的全身及局部（腹部皮下脂肪组织和前臂）去甲肾上腺素（NE）动力学，这些女性在无脂肪体重方面相匹配。通过输注[³H]NE并从桡动脉、主要引流骨骼肌的前臂深部静脉以及引流腹部皮下脂肪的腹部静脉采集血样来测定NE动力学。肥胖受试者的平均全身NE溢出量（2.82±0.49nmol/min）往往高于体重正常受试者（2.53±0.40nmol/min），但差异无统计学意义。体重正常受试者的脂肪组织和前臂NE向血浆中的溢出率（分别为0.91±0.08pmol·100g组织⁻¹·min⁻¹和1.01±0.09pmol·100ml组织⁻¹·min⁻¹）高于肥胖受试者（分别为0.26±0.05pmol·100g组织⁻¹·min⁻¹和0.58±0.11pmol·100ml组织⁻¹·min⁻¹）（P<0.01）。这些结果表明脂肪组织是人类NE代谢的活跃部位。肥胖女性的脂肪组织NE溢出量明显低于体重正常女性，这可能是肥胖者每千克脂肪量脂肪分解率较低的原因。
