Proton-coupled lactate transport across the basolateral membrane of rat jejunal enterocyte was studied using well purified membrane vesicles. L-lactate uptake is stimulated by an inwardly directed H
+ gradient; the effect of the pH difference is drastically reduced by FCCP and by pCMBS; unlabelled L-lactate causes a strong inhibition, whilst furosemide is uneffective. The H
+ gradient-dependent stimulation of L-lactate uptake is significantly inhibited also by SCN
–: this finding could explain results recently reported in the literature in which H
+-lactate symport was not evidenced in basolateral membranes from rat jejunum.
Key words rat jejunum - basolateral membrane uesicles - proton-lactate cotransport