Cell size and the antilipolytic effect of insulin in human subcutaneous adipose tissue

Lipolysis was studied in subcutaneous adipose tissue removed under local or general anaesthesia from subjects with marked difference in body weight and from obese subjects before and after intestinal shunt operations. The release of glycerol was measured in sections of adipose tissue incubated for two hours in bicarbonate buffer containing 4 per cent bovine albumin with no glucose added. The larger fat cells were more insulin sensitive than the smaller. A positive relationship was observed between the fat cell size and the antilipolytic effect of insulin (100 muU/ml). Insulin had no significant effect on the lipolytic effect of the catecholamines, when this is calculated as the increment in the glycerol release above the basal.