Transport of L-ascorbic acid and dehydro-L-ascorbic acid across renal cortical basolateral membrane vesicles.
The uptake of L-ascorbic acid and dehydro-L-ascorbic acid into renal cortical basolateral membrane vesicles has been characterized. The uptake systems for both solutes demonstrate saturation kinetics. The presence of structural analogs of L-ascorbic acid and dehydro-L-ascorbic acid results in cis-inhibition and trans-stimulation. Uptake of each substrate is Na+-independent, proceeding to an endpoint of substrate equilibrium across the vesicular membrane. The transport mechanism(s) for L-ascorbic acid and dehydro-L-ascorbic acid appears to be facilitated diffusion.
D000818:Animals; D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000378:metabolism*; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D002474:Cell-Free System; D003683:Dehydroascorbic Acid / Q000378:metabolism*; D066298:In Vitro Techniques; D007672:Kidney Cortex / Q000378:metabolism*; D008297:Male; D008564:Membrane Potentials; D051381:Rats
D001205:Ascorbic Acid; D003683:Dehydroascorbic Acid