Importance of Dietary Copper in the Formation of Aortic Elastin

Abstract

The elastin content of the aortas of newly hatched chicks is approximately 5% of the wet weight of the aorta. When chicks were fed a diet containing 25 ppm copper, the elastin content increased to 12% by the seventeenth day. When the diet contained less than 1 ppm copper, the elastin content of the aorta increased more slowly and never equalled that of the control chicks. The addition of copper to 27-day-old copper-deficient chicks resulted in an increase in aortic elastin concentration to that of the control chicks by the sixteenth day of supplementation. Radio-isotope studies, using valine-1-C¹⁴ to study the metabolism of elastin, revealed that this protein is relatively inert once formed. The results of these studies suggest that the lesion in copper deficiency affected the synthesis of elastin. Amino acid analysis of elastin from copper-deficient and control chicks revealed that the lysine concentration of the copper-deficient elastin was 3 times that of control elastin.