Glutathione transport systemin HIH3T3 fibroblasts

摘要

The current study characterizes a mediated trans-port for GSH uptake in murine fibroblasts NIH3T3. The presence of GSH mediated transport is indicated by the behaviour of GSH uptake time-course, as well as by kinetic saturation and the specific inhibition of the initial rate of GSH transport. Moreover, a concen-trative GSH uptake has been measured, whose driving force may be due to a change of membrane potential and the direct involvement of ATP. Hyperbolic kinetic saturation shows a single mediated transport with high affinity for GSH (Km = 0.209 ± 0.03 mM). High specificity of this GSH transporter for the entire struc-ture of GSH is also demonstrated. To summarize, GSH uptake into NIH3T3 cells occurs by an active transport system and shows characteristics similar to ATP-dependent mechanisms previously identified in hepa-tocyte membranes. Moreover, a possible physiological role of this GSH transporter related to NIH3T3 cell proliferation has been hypothesized.