Fig. 5.
Kinetics of Na-dependent bile acid uptake in villus cell BBMV from chronically inflamed and MP treated ileum. A) 3H-taurocholate uptake is shown as a function of varying concentrations of extravesicular taurocholate. Isosmolarity was maintained by adjusting the concentration of mannitol. Uptake for all concentrations was determined at 6 s. As the concentration of extravesicular taurocholate was increased, uptake of taurocholate was stimulated and subsequently became saturated in villus cell BBMV in all conditions. B: Lineweaver-Burk plot of these data with Enzfiter yielded kinetic parameters. The diminished maximal rate of uptake of 3H-taurocholate (Vmax) in the chronically inflamed ileum was reversed by MP treatment. Affinity (1/Michaelis constant) for taurocholate uptake, which was significantly diminished during chronic ileitis, was also reversed by MP in chronically inflamed ileum. The data shown are an average of 3 experiments, and each uptake was done in triplicate.