STUDIES IN PORPHYRIA

Abstract
Patients with the genetic liver disease, acute intermittent porphyria (AIP), have a defect in the reductive transformation of steroid hormones that is manifest by the disproportionate generation of 5ß-steroid metabolites from precursor hormones. 5ß-steroid metabolites were earlier shown to be potent inducers experimentally of δ-aminolevulinate synthetase (ALAS), the mitochondrial enzyme that is rate-limiting in porphyrin synthesis, and that is found at high levels of activity in the livers of AIP patients.