Copper concentration and cytochrome-oxidase and ribonuclease activities in the brains of copper-deficient lambs

Abstract

Cytochrome-oxidase and ribonuclease activities in the area of the red nucleus of the brains of swayback lambs and normal lambs of low liver copper content have been compared. Cytochrome-oxidase activity was significantly lower in brain tissue from swayback lambs than in that from clinically normal lambs. No differences in ribonuclease activity were detected. Clinically normal and swayback lambs could be clearly distinguished on the basis of the Cu content of brain tissue. In all cases swayback was associated with brain Cu concentrations of less than 3 [mu]g/g dry weight of tissue. No such clear distinction was apparent on comparing liver Cu concentrations of normal and affected lambs. It is suggested that factors influencing the distribution of Cu between the brain and other tissues may be of importance in the etiology of swayback.