Effects of transforming growth factor beta 1 and basic fibroblast growth factor on lipoprotein lipase activity in primary cultures of chicken (Gallus domesticus) adipocyte precursors.

1. The effect of TGF-beta and bFGF on lipoprotein lipase activity in chicken adipocyte precursors was investigated. 2. Lipoprotein lipase activity was reduced by up to 80% by incubation with TGF-beta whereas bFGF had no effect. 3. Contrary to that found with the 3T3-L1 preadipocyte cell line it was not necessary for TGF-beta to be present prior to the start of differentiation in order to be effective. 4. Incubation of adipocyte precursors with actinomycin D abolished the effect of TGF-beta suggesting that synthesis of a protein effector is required. 5. These results indicate differences in responsiveness to TGF-beta and bFGF between primary chicken adipocyte precursors and some preadipocyte cell lines.