Snitker S, Pratley R E, Nicolson M, Tataranni P A, Ravussin E
Clinical Diabetes and Nutrition Section, National Institute of Diabetes and Digestive and Kidney Diseases, national Institutes of Health, Phoenix, AZ 85016, USA.
Obes Res. 1997 Jul;5(4):338-40. doi: 10.1002/j.1550-8528.1997.tb00561.x.
In humans, basal muscle sympathetic nerve activity (MSNA), a direct measure of sympathetic nervous outflow, is correlated with percentage of body fat. The underlying physiological mechanism is unknown. On the basis of the observation that leptin increases sympathetic nervous outflow in the ob/ob mouse, we hypothesized that leptin, a hormone secreted by the adipose tissue, may act as a peripheral signal to increase sympathetic nervous outflow from the central nervous system. We therefore tested whether basal MSNA is correlated with plasma leptin concentration. Fasting plasma samples and recordings of basal MSNA in the peroneal nerve were obtained from 37 healthy, nondiabetic men (35 whites and 2 Mexican-Americans; 29 +/- 7 years, 86 +/- 14 kg, 24 +/- 10% body fat; mean +/- SD) who were fed a weight-maintenance diet on a metabolic ward. As expected, plasma leptin concentration (geometric mean, 6.4 ng/mL; 95% confidence interval, 4.6 ng/mL to 9.0 ng/mL) correlated with % body fat (r = 0.93, p < 0.001). Basal MSNA was 31.6 +/- 10.0 bursts/min and correlated with % body fat (r = 0.53, p < 0.001) and with plasma leptin concentration (r = 0.44, p < 0.01). In conclusion, the results demonstrate a correlation between MSNA and plasma leptin concentration of a magnitude similar to that between MSNA and % body fat. Leptin may therefore be the peripheral signal explaining the correlation between MSNA and % body fat. A full understanding of the relationship between leptin and the activity of the sympathetic nervous system requires further studies, including the administration of leptin in humans.
在人类中，基础肌肉交感神经活动（MSNA）是交感神经传出的直接指标，与体脂百分比相关。其潜在的生理机制尚不清楚。基于瘦素可增加ob/ob小鼠交感神经传出的观察结果，我们推测，由脂肪组织分泌的一种激素——瘦素，可能作为一种外周信号来增加中枢神经系统的交感神经传出。因此，我们测试了基础MSNA是否与血浆瘦素浓度相关。从37名健康的非糖尿病男性（35名白人，2名墨西哥裔美国人；年龄29±7岁，体重86±14千克，体脂24±10%；均值±标准差）中获取空腹血浆样本以及腓神经基础MSNA的记录，这些男性在代谢病房中进食维持体重的饮食。正如预期的那样，血浆瘦素浓度（几何均值，6.4 ng/mL；95%置信区间，4.6 ng/mL至9.0 ng/mL）与体脂百分比相关（r = 0.93，p < 0.001）。基础MSNA为31.6±10.0次/分钟，与体脂百分比相关（r = 0.53，p < 0.001），也与血浆瘦素浓度相关（r = 0.44，p < 0.01）。总之，结果表明MSNA与血浆瘦素浓度之间的相关性大小与MSNA与体脂百分比之间的相似。因此，瘦素可能是解释MSNA与体脂百分比之间相关性的外周信号。要全面理解瘦素与交感神经系统活动之间的关系，还需要进一步研究，包括在人体中施用瘦素。
