CHANGES IN TISSUE CONTENTS OF ZINC, COPPER AND IRON IN RATS AND BEAGLE DOGS TREATED WITH POLAPREZINC

Abstract

Zinc, copper and iron levels of tissues in rats or beagle dogs were measured after a 13- or 52-week toxicity study of polaprezinc, which contains a zinc element; The zinc content in almost all rat tissues remarkably increased with a conspicuous decrease of copper and various changes of iron at doses of 600 mg/kg/day or more. Zinc and copper levels increased and decreased respectively, at 300 mg/kg/day. At a dose of 150 mg/kg/day, there was a slight increase of zinc in some tissues at 52-weeks, but no copper decrease. The results obtained from beagle dogs differed somewhat from that in rats. Dogs treated with polaprezind at 50 mg/kg/day or more accumulated zinc in some tissues. A copper decrement was seen only in the liver and heart from the group given 300 mg/kg/day, whereas copper levels in the kidney of all treated groups were higher than that in the controls suggesting that canine polaprezinc toxicity is due to direct zinc toxic effects.