Patel J N, Eisenhofer G, Coppack S W, Miles J M
Clinical Neuroscience Branch, National Institutes of Health, Bethesda, Maryland 20892, USA.
J Clin Endocrinol Metab. 1999 Aug;84(8):2815-9. doi: 10.1210/jcem.84.8.5882.
The sympathetic nervous system regulates lipolysis. There are regional differences in the sensitivity of lipolysis to adrenergic regulation. Little is known about regional sympathetic activity in response to eating in humans. We studied the effect of feeding on systemic and local sympathetic nervous system activity and lipolysis in lean healthy subjects (three women and five men; age, 27.0+/-2.0; body mass index, 23.4+/-1.2 kg/m(-2)) using isotope dilution methodology and arterio-venous sampling. Feeding increased arterial norepinephrine (NE) concentration (mean premeal, 0.96+/-0.12 nmol/L x L; mean postmeal, 1.28+/-0.14 nmol/L x L; P < 0.02) and total body NE spillover (mean premeal, 2.11+/-0.30 nmol/min x L; mean postmeal, 2.76+/-0.31 nmol/min x L; P < 0.02), whereas the arterial epinephrine concentration decreased (mean premeal, 289+/-61 pmol/L; mean postmeal, 170+/-5 pmol/L; P < 0.02). Palmitate concentration and total body systemic rate of appearance of palmitate declined postprandially (mean premeal, 117 +/- 15 micromol/min; mean postmeal, 38+/-4 micromol/min; P < 0.01). NE spillover increased by the same proportion in both forearm and adipose tissue [in forearm, mean premeal and postmeal, 1.02+/-0.11 and 2.41+/-0.44. nmol/100 mL x min, respectively (P < 0.02); in adipose tissue, mean premeal and postmeal, 0.41+/-0.12 and 0.73+/-0.17 nmol/100 g x min, respectively (P < 0.02)]. The results show that a meal caused differential changes in systemic sympatho-adrenal activity and an increase in sympathetic activity in adipose tissue postprandially, However, this increase in postprandial sympathetic activity was not enough to overcome the inhibition of lipolysis by insulin.
交感神经系统调节脂肪分解。脂肪分解对肾上腺素能调节的敏感性存在区域差异。关于人类进食后局部交感神经活动知之甚少。我们采用同位素稀释法和动静脉采样，研究了进食对健康瘦人（3名女性和5名男性；年龄27.0±2.0岁；体重指数23.4±1.2kg/m²）全身和局部交感神经系统活动及脂肪分解的影响。进食使动脉去甲肾上腺素（NE）浓度升高（餐前均值0.96±0.12nmol/L×L；餐后均值1.28±0.14nmol/L×L；P<0.02）以及全身NE溢出增加（餐前均值2.11±0.30nmol/min×L；餐后均值2.76±0.31nmol/min×L；P<0.02），而动脉肾上腺素浓度降低（餐前均值289±61pmol/L；餐后均值170±5pmol/L；P<0.02）。餐后棕榈酸浓度和全身棕榈酸出现率下降（餐前均值117±15μmol/min；餐后均值38±4μmol/min；P<0.01）。前臂和脂肪组织中NE溢出增加的比例相同[在前臂，餐前和餐后均值分别为1.02±0.11和2.41±0.44nmol/100mL×min（P<0.02）；在脂肪组织中，餐前和餐后均值分别为0.41±0.12和0.73±0.17nmol/100g×min（P<0.02）]。结果表明，一餐引起全身交感-肾上腺活动的不同变化，并使餐后脂肪组织中的交感神经活动增加。然而，餐后交感神经活动的这种增加不足以克服胰岛素对脂肪分解的抑制作用。
