Pharmacological adrenalectomy with mitotane

The potential of mitotane (ortho, para'-DDD, commonly used to treat adrenal carcinomas in humans and dogs) was investigated as an alternative to surgi cal adrenalectomy in birds, salamanders, and lizards. House sparrows (Passe r domesticus) were injected twice daily with vehicle or one of two doses of mitotane (225; or 450 mg/kg), and basal and stress-induced levels of corti costerone (CORT) were measured 3 and 5 days after injections. Mitotane redu ced basal CORT levels to nondetectable and abolished stress-induced CORT in creases by the 3rd day of treatment. In another study, a single injection o f mitotane was effective in lowering endogenous CORT levels 36 h later, but levels had apparently recovered by 10 days after the injection. Mitotane d id not effect testicular weights and had no detectable effect on testostero ne levels. In contrast to its effects on house sparrows, mitotane did not l ower endogenous CORT levels in either tiger salamanders (Ambystoma tigrinum ) or tree lizards (Urosaurus ornatus), even at doses much higher than those used in house sparrows. (C) 2000 Academic Press.