This study was carried out to verify the hypothesis of a link between faster endogenous phosphorylation of band 3 protein, the anion carrier, and anomalous oxalate transmembrane self-exchange found in erythrocyte from calcium oxalate renal stone formers. Agents able to modify 32P-labelling of band 3 protein induced a concurrent modification in oxalate transmembrane flux. Cyclic AMP- and phospholipid-sensitive Ca(2+)-independent protein kinases seem to be critical modulators of band 3 function. These observations demonstrate a close link between the band 3 phosphorylation state and its anion transport function, and provide new insights into the pathogenetic mechanisms of the cellular anomalies observed in calcium-oxalate renal stone disease.