Induction of xCT gene expression and L-cystine transport activity by diethyl maleate at the inner blood-retinal barrier.

摘要: PURPOSE. In this study, the expression and regulation of L-cystine transporter, system xc , at inner blood–retinal barrier (inner BRB) was investigated using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB2) as an in vitro model. METHODS. For uptake TR-iBRB2 cells were cultured 33°C presence or absence diethyl maleate (DEM), rate [ 14 C]L-cystine measured 37°C. The mRNA levels which consists xCT 4F2hc, determined by quantitative real-time RT-PCR analysis with specific primers. RESULTS. 4F2hc mRNAs expressed TRiBRB2 cells. appeared to be mediated through saturable Na-independent process. corresponding Michaelis-Menten constant 9.18 M. At 100 M DEM, level activity enhanced timedependent manner. Concomitantly, glutathione concentration increased. contrast, unchanged up 24 hours induced for more than DEM treatment. Under both normal treatment conditions, strongly inhibited L-glutamic acid, L--aminoadipic L-homocysteic L-quisqualic whereas L-aspartic acid L-arginine had no effect, is evidence induction . CONCLUSIONS. System -mediated appears present BRB. induces transport BRB transcription gene. (Invest Ophthalmol Vis Sci. 2002;43: 774 –779)