Epididymal aldehyde dehydrogenase: a pharmacologic profile.

The in vivo effect of various agents, with different pharmacologic properties, on cytosolic EP-ALDH was studied in the rat. Injection of a large dose of PYZ inhibited EP-ALDH 16 h after the injection. Short-term administration of a moderate daily dosage of PYZ also inhibited endogenous EP-ALDH from saline controls. Semichronic administration of a small daily dosage of DIS resulted in inhibition of EP-ALDH. Short-term administration of drugs with various pharmacologic profile produced little change in the specific activity of EP-ALDH. This is compared with an induction and an inhibition of T-ALDH as a function of treatment with an antiandrogen and an estrogenic drug, respectively. The results show lack of response of EP-ALDH towards pharmacologic intervention which may imply certain specificity for EP-ALDH.