Effect of Treatment with Hemin on Rat Liver Catalase

Abstract

Rats were injected with a single or repeated doses of heroin intraperitoneally, and the effect on liver catalase [EC 1. 11. 1. 6] was studied. A single administration of hemin caused a reduction in the concentration of liver catalase, both in enzymatic activity and in catalase protein determined immunochemically. The reduction occurred a few hours after the hemin injection, and is probably due to stimulated degradation. Disappearance of radioactivity from liver catalase prelabelled with [¹⁴C]leucine was enhanced following the administration of hemin. No evidence for a repression in vivo incorporation of [¹⁴C]leucine and [³H]δ-aminolevulinic acid into liver catalase was obtained with hemin-treated rats. When the hemin was given repeatedly at 12-h intervals, the level of liver catalase decreased considerably. However, the impairment in catalase-synthesizing activity of liver cells of rats thus treated was rather slight, when examined in a cell-free system. Some differences were noted between the results in the present study and those in previous investigations with Sedormid-treated rats.