Hyperlipidemia is a common occurance in patients with chronic renal failure (CRF) and has been the subject of many clinical and experimental studies. Despite this, the role of lipogenesis in the development of hyperlipidemia is still obscure. The present study is based on a rat model of CRF involving a two-stage subtotal nephrectomy. In this study, we measured the activity of fatty acid synthase (FAS). This is the rate-limiting enzyme of lipogenesis and is present in liver and white adipose tissue (WAT). Using isotopic methods, we also determined the rate of lipogenesis in vivo in liver and WAT. In both liver and WAT, the results of the analyses were similar. In the uremic rats, there was a tendency for the FAS activity to rise. However, the difference was not statistically significant. Furthermore, there was no increase in the rate of lipogenesis in vivo in either tissue. In summary, the results of our study confirm the thesis that lipogenesis does not play a role in the development of hypertriglyceridemia seen in an experimental CRF in rats.