AZT inhibition of the ADP/ATP antiport in isolated rat heart mitochondria

In order to gain insight into the mechanism by which AZT affects mitochondr ial metabolism in heart, lending to the ATP deficiency syndrome, the capabi lity of AZT to affect certain mitochondrial translocators was checked in co upled mitochondria isolated from rat heart. AZT was found to strongly inhib it the ADP/ATP antiport, in a competitive manner (K-i 7 mu M), as photometr ically measured. Contrarily, the rate of the succinate/malate exchange via the dicarboxylate carrier, of the oxaloacetate uptake via the oxodicarboxyl ate carrier and of cis-aconitate uptake via the tricarboxylate carrier was found to be unchanged in the presence of AZT.