A NEW TECHNIQUE FOR BIOPSY OF HUMAN ABDOMINAL FAT UNDER LOCAL-ANESTHESIA WITH LIDOCAINE

The objectives of this study were to develop a new technique to safely , reliably, and in a cosmetically acceptable way, obtain more than 5.0 g of abdominal subcutaneous fat in out-patients, and to investigate w hether inhibitory effects of a local anaesthetic on adipose tissue fun ction in vitro are sufficient argument against the use of infiltrative local anaesthesia during fat biopsy to obtain samples for metabolic s tudies. Measurements were obtained to compare glucose transport and li polysis response to insulin in adipocytes isolated from subcutaneous a bdominal fat obtained: (i) during elective surgery in eight women and four men (BMI 25.8 +/- 3.1 kg/m(2)); and (ii) from five male and three female out-patients (BMI 25.8 +/- 3.1 kg/m(2)) by the described novel technique performed under local anaesthesia with Lidocaine. The effec ts of acute and 11-day exposure to Lidocaine in vitro on adipocyte lip olysis and glucose transport response to insulin, and the growth poten tial were determined. In vivo exposure of the tissue samples to local anaesthetic by the novel technique had no apparent effect on isolated adipocyte responses to insulin by stimulation of glucose transport or by inhibitor- or adrenaline-stimulated lipolysis; the results were not different to those for adipocytes isolated from fat obtained during e lective abdominal surgeries. Lidocaine added in vitro potently inhibit ed glucose transport and lipolysis in adipocytes, and cell attachment and growth in primary 'ceiling' culture; this effect persisted only as long as Lidocaine was present. After washing, adipocytes fully regain ed their function and growth regardless of the exposure period, as sho rt as 30 min or as long as 11 days. Therefore, the proposed novel tech nique allows rapid sampling of significant amounts of abdominal fat in outpatients. Lidocaine has an inhibitory effect on adipocyte function ; however, this effect appears to be fully reversible.