Figure 4.

Aspartate Flux. (A) Cells were serum starved for 24 h prior to stimulation with 100 nm recombinant Human Insulin for 7 h in the presence of 2uCi/ml U-¹⁴C aspartate and 1uCi/ml [5,6-³H] uridine. The radiolabeled U-¹⁴C aspartate incorporated into total RNA was normalized to the amount of [5,6-³H] uridine incorporated into RNA. Controls represent the averages of two separate fibroblast lines, GM00038 and GM03348. (B) Cells were serum starved for 24 h prior to stimulation with 100 nm recombinant Human Insulin for 7 h in the presence of 2 mm ¹³C,¹⁵N aspartate. Hydrolyzed samples were analyzed via GCMS. No difference was observed for incorporation of ¹³C aspartate into adenine. Controls represent the averages of two separate control fibroblast lines GM00038 and GM03348.