Abstract
Aims/hypiothesis Obesity is characterised by increased triacylglycerol storage in adipose tissue. There is in vitro evidence for a blunted beta-adrenergically mediated lipolytic response in abdominal subcutaneous adipose tissue (SAT) of obese individuals and evidence for this at the whole-body level in vivo. We hypothesised that the beta-adrenergically mediated effect on lipolysis in abdominal SAT is also impaired in vivo in obese humans. Methods We investigated whole-body and abdominal SAT glycerol metabolism in vivo during 3 h and 6 h [H-2(5)]glycerol infusions. Arterio-venous concentration differences were measured in 13 lean and ten obese men after an overnight fast and during intravenous infusion of the non-selective beta-adrenergic agonist isoprenaline [20 ng (kg fat free mass)(-1)min(-1)]. Results Lean and obese participants showed comparable fasting glycerol uptake by SAT (9.7 +/- 3.4 vs 9.3 +/- 2.5% of total release, p=0.92). Furthermore, obese participants showed an increased whole-body beta-adrenergically mediated lipolytic response versus lean participants. However, their fasting lipolysis was blunted [glycerol rate of appearance: 7.3 +/- 0.6 vs 13.1 +/- 0.9 mu mol (kg fat mass)(-1)min(-1), p
Original language | English |
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Pages (from-to) | 320-327 |
Journal | Diabetologia |
Volume | 51 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1 Jan 2008 |