As adipose tissue is usually obtained during local or general anesthesia in clinical studies, these two forms of anesthesia were presently compared as regards lipolysis induced by catecholamines in isolated human fat cells. Fat samples from the abdominal subcutaneous region were obtained first during local anesthesia (lidocaine) given so that the anesthetic agent did not influence lipolysis and second, during gastric banding under general anesthesia (propofol) immediately after skin incision. Eleven obese patients, drug free and otherwise healthy. Isolated fat cells were incubated in the presence or absence of increasing concentrations of different lipolysis agents, acting at adrenoceptor or various post-receptor levels in the lipolytic cascade. Glycerol release to the incubation medium was measured as an index of lipolysis. All agonists caused a concentration dependent increase (terbutaline, dobutamine, CGP 12177, forskolin, dibutyryl cyclic AMP, isoprenaline and noradrenaline) or inhibition (clonidine) of glycerol release. The comparison of data from local and general anesthesia procedures showed no statistical difference in glycerol response for any of the drugs used. Adrenergic regulation of lipolysis is not influenced by the mode of sampling, at least not in subcutaneous fat cells of obese subjects obtained during local anesthesia with lidocaine as compared to general anesthesia with propofol.