Inhibition of Sulphate and Selenate Transport in Sheep Jejunum by Oxalate and Other Dicarboxylate Anions¹

Abstract

The influence of oxalate on mucosal sulphate, selenate and selenite uptake in the sheep midjejunum was investigated. Oxalate significantly inhibited sulphate and selenate uptake, whereas mucosal uptake of selenite and L-leucine was not affected. Thus, the effect of oxalate on sulphate and selenate uptake appears to be specific. Besides oxalate, the dicarboxylate anions oxaloacetate and fumarate also significantly reduced mucosal sulphate uptake.The results suggest that oxalate and dicarboxylate anions with a similar structure competitively inhibit mucosal sulphate and selenate uptake by sheep mid-jejunum.