Copper distribution in the neonatal rat

Abstract

Liver copper concentration in the neonatal rat rises from birth, reaches a peak by the 16th day, then decreases to adult concentrations. Total plasma Cu is lowest at birth, increases within 24 hr and remains constant throughout development. Although increasing progressively from birth, low ceruloplasmin oxidase activity was found throughout development. ACTH administered daily for at least 4 days prevented normal ceruloplasmin increase. Nonceruloplasmin plasma Cu was highest during the first 3 weeks of life but decreased after weaning. Cortisone and corticosterone injections at birth produced liver Cu decrements. Cu injections produced a profound rise in liver Cu concentration but failed to influence the ceruloplasmin activity. Newborns from mothers on a Cu-deprivation diet had lower than normal liver Cu, whereas mothers receiving Cu, cortisone, and Adrenalin injections produced offspring with liver Cu concentrations significantly higher than normal. Single doses of adrenalin, ACTH, alpha MSH [melanocyte stimulating hormone], testosterone, and estrone administered at birth failed to produce any changes in liver or plasma Cu concentration.