Degradation ofEndogenous Hepatic HemebyPathways NotYielding CarbonMonoxide

Theconversion ofendogenous hepatic hemetobilirubin andCOisestablished. However, itis unknown whether this process isquantitative orwhether hememaybedegraded toother products aswell. To study this question, weadministered thehemeprecur- sor, 8-amino-(5-'4C)levulinic