Carrier-mediated transport of urate by chicken (Gallus domesticus) renal brush-border membrane vesicles.

1. Urate is transported by an anion exchange system in chicken renal brush-border membrane vesicles. An outward chloride gradient stimulates an overshoot in urate uptake. 2. The anion exchanger is similar to those described for the kidneys of rats and dogs except that the chicken exchanger has a higher specificity for urate. 3. p-Aminohippurate has only a weak affinity, if any, for the urate exchanger. 4. There were no apparent qualitative differences in urate transport between brush-border membrane vesicles from genetically normouricemic and hyperuricemic chickens.