KINETICS OF HEPATIC HEME TURNOVER IN RATS GIVEN ALLYLISOPROPYLACETAMIDE: A NEW MODEL FOR LIVER HEME CATABOLISM

Kinetic analysis of hepatic heme turnover, for 49h after labelling with 14 C-δ-aminolevulinate (ALA), revealed the existence of two heme pools. A single injection of allylisopropylacetamide, 4h after 14 C-ALA, led to production of “green pigments” and increased heme turnover. This increased turnover was due to an increase in the size of the more rapidly turning-over pool, not to an increase in the rate constants for turnover from either pool. Green pigments also underwent rapid biphasic turnover.