Influence of hypocaloric diet on alpha-adrenergic responsiveness of obese human subcutaneous adipocytes.
Spontaneous and stimulated lipolytic activity of subcutaneous abdominal adipocytes from obese subjects treated by a hypocaloric diet (800-1000 kcal/d) for 13-15 d were studied. A strong increase in basal lipolytic activity of the adipocytes occurred after the restrictive diet treatment. Linked to this phenomenon, an important alpha-adrenergic antilipolytic effect of adrenaline appeared whereas, the beta-stimulating effect of isoproterenol (beta-adrenomimetic drug) was not affected. The increased alpha-inhibitory effect of adrenaline was shown to theophylline-stimulated adipocytes of energy-restricted subjects. It is concluded that after a period of hypocaloric diet, the adrenaline-dependent lipolysis of subcutaneous abdominal fat cells of obese subjects is reversed. The lipolytic response induced by adrenaline, described in the adipocytes of obese controls, develop towards an alpha-adrenergic antilipolytic response after the hypocaloric treatment. Our data suggest that, in states with increased rate of lipolysis, there is an increased readiness for alpha-adrenergic response.
D000273:Adipose Tissue / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D004038:Diet, Reducing; D002149:Energy Intake; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D066298:In Vitro Techniques; D008066:Lipolysis; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy / Q000378:metabolism*; D011433:Propranolol / Q000494:pharmacology; D011941:Receptors, Adrenergic / Q000378:metabolism*; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*; D013806:Theophylline / Q000494:pharmacology
D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D011433:Propranolol; D013806:Theophylline; D004837:Epinephrine