RT Journal Article SR Electronic T1 Biphasic Decrease of Radioactive Hemoprotein from Liver Microsomal Carbon Monoxide-Binding Particles JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 499 OP 506 VO 5 IS 5 A1 W. LEVIN A1 R. KUNTZMAN YR 1969 UL http://molpharm.aspetjournals.org/content/5/5/499.abstract AB The administration of δ-aminolevulinic acid-3,5-3H to immature male rats leads to the incorporation of radioactivity into hemoprotein in the CO-binding particles. The incorporated radioactivity decreases in two distinct phases: a rapid phase with a half-life of 7-8 hr and a slow phase with a half-life of 46-48 hr. Treatment with phenobarbital or chlordane does not appreciably after the ratio of the fast-phase component to the slow-phase component but does increase the half-life to the fast phase of 11-12 hr. The increase in the protoheme content of the CO-binding particles found after phenobarbital and chlordane treatment suggests that these compounds increase the amount of both the rapidly and slowly decaying components.