Plasma leptin response to an epinephrine infusion in lean and obese women.
OBJECTIVE
Because leptin production by adipose tissue is under hormonal control, we examined the impact of epinephrine administration on plasma leptin concentrations.


METHODS
We measured plasma leptin, insulin, and free fatty acid (FFA) responses after a 60-minute epinephrine infusion (0.010 microg/kg fat free mass/min) followed by a 30-minute recovery period (no infusion) in a group of 11 lean (mean body mass index +/- SD: 22.6 +/- 1.1 kg/m(2)) and 15 obese (30.0 +/- 1.3 kg/m(2)) premenopausal women. Leptin, insulin, and FFA levels were measured in plasma before (-15 and 0 minutes) and at every 30 minutes over the 90-minute period.


RESULTS
In both lean and obese individuals, plasma leptin was significantly reduced by epinephrine (p < 0.0001). Body fat mass was associated with fasting leptin levels (r = 0.64, p < 0.0005) as well as with the decrease in leptinemia (r = -0.51, p < 0.01) produced by epinephrine administration. Furthermore, we noted a large range of leptin response to epinephrine among our subjects, especially in obese women (from -12 to -570 ng/mL per 60 minutes). However, there was no association between postepinephrine leptin and FFA levels (r = -0.14, p = 0.55).


CONCLUSIONS
Results of this study indicate that leptin levels decrease after epinephrine administration in both lean and obese premenopausal women. However, the heterogeneity in the response of leptin to catecholamines suggests potential alterations of the leptin axis that may contribute to generate a positive energy balance and, thus, may favor weight gain in some obese individuals.
Couillard
Charles
C
Department of Food Science and Nutrition, Laval University, Sainte-Foy, Québec, Canada.
Mauriège
Pascale
P
Prud'homme
Denis
D
Nadeau
André
A
Tremblay
Angelo
A
Bouchard
Claude
C
Després
Jean-Pierre
JP
D000322:Adrenergic Agonists / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D000328:Adult; D019540:Area Under Curve; D001786:Blood Glucose / Q000032:analysis; D004837:Epinephrine / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007262:Infusions, Intravenous; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood*; D009765:Obesity / Q000097:blood*; D017697:Premenopause / Q000097:blood
D000322:Adrenergic Agonists; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D020738:Leptin; D004837:Epinephrine