concomitant with heme oxygenase induction by antimony , microsomal heme and cytochrome p-450 contents decreased , the cyto-chrome p-450-dependent mixed function oxidase system was impaired , and delta-ami-nolevulinate synthase ( alas ) , the rate-limiting enzyme of heme synthesis , underwent the sequential changes-initial inhibition followed by rebound induction-usually associated with the administration of transition elements such as cobalt .
C0018969
heme oxygenase
C0020364
mixed function oxidase