Circulating concentrations of fatty acids are elevated in obesity, although their effect on regional fat deposition is relatively unexplored. With the increasing prevalence of childhood obesity, we aimed to investigate whether saturated and unsaturated fatty acids lead to differential lipid accumulation (LA) in children's subcutaneous and visceral adipocytes. To examine this, subcutaneous and peri-nephric pre-adipocytes, isolated from fat biopsies from 6 pre-pubertal children, were differentiated in vitro before being exposed to palmitate and/or oleate for 24 h. Lipid accumulation was then quantified by nile red staining. Palmitate significantly increased LA in visceral adipocytes at all doses >= 188 mu M (e.g. Palmitate 750 mu M: +30.0%[8.2]; p < 0.01), whilst only a dose of 375 mu M led to a significant, but smaller, increase in LA in subcutaneous adipocytes (Palmitate 375 mu M: +13.0%[4.3]; p = 0.02). In contrast, oleate significantly increased LA in subcutaneous (Oleate 1000 mu M: +36.3%[14.0]; p = 0.01), but not visceral (Oleate 1000 mu M: +16.2%[9.6]; p = 0.25) adipocytes. These data suggest that saturated and unsaturated fatty acids may exert depot-specific effects on lipid accumulation. (c) 2007 Elsevier Inc. All rights reserved.