EFFECTS OF ACUTE AND CHRONIC HEMOLYSIS ON IRON METABOLISM IN SPRAGUE-DAWLEY RAT

The rate of iron excretion was measured weekly in three groups of female Charles River Sprague-Dawley rats (269 [plus or minus] 4.4 g) over a period of 112 days. All three groups (19 rats) were maintained on Purina laboratory chow with an Fe content of 275 ppm. Two of the groups (13 rats) received weekly injections of phenylhydrazine in doses of 25 mg/kg or 50 mg/kg intraperitoneally. The third group (controls) received weekly saline injections. Subsequently the total body Fe in each of the 19 rats was determined. It was found that the daily excretory rate of Fe in the control rats (0.24 percent) was lower than that occurring in the rats treated with phenylhydrazine, 25 mgAg and 50 mg/kg (0.28 percent and 0.34 percent, respectively). Similarly total-body Fe in the control rats (4.2 mg/100 g body wt) was lower than that occurring in the phenylhydrazine-treated rats (6.5 mg/100 g and 9.8 mg/100 g). Moreover this difference was statistically significant (P < 0.01). The biliary excretion of Fe was followed in nine rats after saline or phenylhydrazine injections. Peak Fe excretion occurred 3 and 4 hr. after injection in those rats receiving phenylhydrazine 25 mg/kg and 50 mg/kg, respectively.