Moro Cedric, Pillard Fabien, de Glisezinski Isabelle, Klimcakova Eva, Crampes Francois, Thalamas Claire, Harant Isabelle, Marques Marie-Adeline, Lafontan Max, Berlan Michel
INSERM U858-I2MR, Institut de Médecine Moléculaire de Rangueil, 1 Ave. Jean Poulhès, Toulouse Cedex 4, France.
Am J Physiol Endocrinol Metab. 2008 Aug;295(2):E505-13. doi: 10.1152/ajpendo.90227.2008. Epub 2008 Jun 17.
Involvement of sympathetic nervous system and natriuretic peptides in the control of exercise-induced lipid mobilization was compared in overweight and lean men. Lipid mobilization was determined using local microdialysis during exercise. Subjects performed 35-min exercise bouts at 60% of their maximal oxygen consumption under placebo or after oral tertatolol [a beta-adrenergic receptor (AR) antagonist]. Under placebo, exercise increased dialysate glycerol concentration (DGC) in both groups. Phentolamine (alpha-AR antagonist) potentiated exercise-induced lipolysis in overweight but not in lean subjects; the alpha(2)-antilipolytic effect was only functional in overweight men. After tertatolol administration, the DGC increased similarly during exercise no matter which was used probe in both groups. Compared with the control probe under placebo, lipolysis was reduced in lean but not in overweight men treated with the beta-AR blocker. Tertatolol reduced plasma nonesterified fatty acids and insulin concentration in both groups at rest. Under placebo or tertatolol, the exercise-induced changes in plasma nonesterified fatty acids, glycerol, and insulin concentrations were similar in both groups. Exercise promoted a higher increase in catecholamine and ANP plasma levels after tertatolol administration. In conclusion, the major finding of our study is that in overweight men, in addition to an increased alpha(2)-antilipolytic effect, the lipid mobilization in subcutaneous adipose tissue that persists during exercise under beta-blockade is not dependent on catecholamine action. On the basis of correlation findings, it seems to be related to a concomitant exercise-induced rise in plasma ANP when exercise is performed under tertatolol intake and a decrease in plasma insulin.
在超重和体重正常的男性中，比较了交感神经系统和利钠肽在运动诱导的脂质动员控制中的作用。在运动期间使用局部微透析法测定脂质动员情况。受试者在服用安慰剂或口服酒石酸美托洛尔（一种β-肾上腺素能受体拮抗剂）后，以其最大耗氧量的60%进行35分钟的运动。在服用安慰剂的情况下，运动使两组的透析液甘油浓度（DGC）均升高。酚妥拉明（α-肾上腺素能受体拮抗剂）增强了超重受试者而非体重正常受试者运动诱导的脂肪分解；α₂抗脂肪分解作用仅在超重男性中起作用。服用酒石酸美托洛尔后，无论在两组中使用哪种探头，运动期间DGC的升高情况相似。与服用安慰剂时的对照探头相比，β-肾上腺素能受体阻滞剂治疗的体重正常男性的脂肪分解减少，但超重男性未减少。酒石酸美托洛尔使两组静息时的血浆非酯化脂肪酸和胰岛素浓度降低。在服用安慰剂或酒石酸美托洛尔的情况下，两组运动诱导的血浆非酯化脂肪酸、甘油和胰岛素浓度变化相似。服用酒石酸美托洛尔后，运动促进了儿茶酚胺和心房钠尿肽血浆水平的更高升高。总之，我们研究主要发现是，在超重男性中，除了α₂抗脂肪分解作用增强外，在β受体阻滞剂作用下运动期间皮下脂肪组织中持续存在的脂质动员不依赖于儿茶酚胺作用。根据相关性研究结果，这似乎与在服用酒石酸美托洛尔进行运动时运动诱导的血浆心房钠尿肽升高以及血浆胰岛素降低有关。
