TABLE 1

Influence of Li⁺ on the activity of the wild-type and mutant human NaCTs

Wild-type and mutant human NaCT cDNAs were expressed in HRPE cells using the vaccinia virus expression technique, and the activity of the expressed transporters was monitored by the uptake of citrate (10 μM) in a NaCl-containing buffer in the absence and presence of Li⁺ (10 mM). The experiments were repeated 3 times with independent transfections, and uptake measurements were made in duplicate in each experiment. Uptake of citrate in cells transfected with vector alone was negligible. Data (mean ± S.E.) represent cDNA-specific uptake.