Effects of fasting on lipoprotein lipase activity in different depots of white and brown adipose tissues in diet-induced overweight rats

The aim of the present study was to evaluate the effects of 24 hours of sta rvation on lipoprotein lipase (LPL) activity in various depots of white and brown adipose tissues in control rats and in rats with two different degre es of overweight, both induced by dietary treatment. In control rats, no ch anges in LPL immunoreactive mass were observed in either white or brown adi pose tissues after fasting, whereas the effects of food deprivation on enzy me activity were opposite in white versus brown adipose tissues. The LPL ac tivity response to fasting was impaired by obesity: White adipose depots of cafeteria obese rats showed a lower ability to downregulate LPL during fas ting and the increased LPL activity induced by fasting in brown adipose dep ots was less intense in the obese mts compared with control animals. When t he degree of overweight was reduced, the differences between obese and cont rol mts were also attenuated (C) Elsevier Science inc. 1999. All rights res erved.