STUDIES ON COPPER METABOLISM

Abstract

The results of studies on certain enzymes, hemin chromoproteins, and iron and copper in the tissues of normal, copper-deficient, and iron-deficient swine are reported in this paper.It has been suggested that the enzymes cytochrome oxidase (l-3), uricase (4), tyrosinase (5), plasma polyphenol oxidase (coeruloplasmin) (6), glutathione oxidase (7), and butyryl coenzyme A dehydrogenase (8) either contain copper or are associated with copper in their activity.Accordingly a study of the activity of these enzymes in the tissues has been included.The tissue hemin chromoproteins, cytochrome oxidase, cytochrome c, catalase, and myoglobin, were studied because of evidence from earlier work (9, 10) that hemoglobin synthesis is impaired and that copper influences the metabolism of iron.Inconsistencies and scarcity of reported data on the hemin chromoprotein content of the tissues in copper and iron deficiencies provided additional reasons for this study. MethodsThe twenty-three swine used in this study were part of a larger group used in studies of the hematological manifestations of copper and iron deficiencies (11).The details of the care and feeding of these animals have been described ( 9).The diet consisted of a commercial brand of canned evaporated milk diluted 1: 1 with water.Six pigs received both iron and copper as supplements (30 mg. and 0.5 mg., respectively, per kilo per day), and served as the control group.Fifteen received only iron in the above amount (copper-deficient) and three received only copper (iron-deficient).Five of the copper-deficient pigs received a total of 1000 mg. of iron intravenously as saccharated oxide of iron' prior to the development of anemia.100 mg. of iron were administered three times a week to these animals.Uric acid and allantoin determinations were made on 24 hour samples