Intact ferrets have negative feedback of steroids to regulate the release of LHRH which then leads to the secretion of LH. The lighting works with the release of , tryptophan, seretonin, then to melatonin. Melatonin works when an enzyme (HIOMT) is activated by darkness. If this is absent LHRH goes up. Without negative feedback from the gonads, secretion increases. Now the adrenal glands have LH receptors but no neg. feedback. Therefore endocrine aspects have a major influence of adrenal disease. Andria Ludwig Department of Animal Science Michigan State Unversity [Posted in FML issue 5216]