Figure 1.

Time course (A) and kinetics (B) of ¹⁴C-l-methionine (¹⁴C-l-Met) uptake by normal trophoblast (NTB) and diabetic trophoblast (DTB) cells. For time course experiments, cells were incubated for various periods of time at 37°C with 250 nmol/L ¹⁴C-l-Met, pH 7.5 (n = 6-7, from 3 distinct placenta). For kinetic experiments, initial rates of uptake were determined in cells incubated at 37°C with increasing concentrations of ¹⁴C-l-Met (0.25-50 μmol/L) for 6 minutes (n = 9-12, from 3 to 4 distinct placenta). Shown is arithmetic mean ± standard error of the mean.