Binding of EDTA, Histidine and Acetylsalicylic Acid to Zinc–Protein Complex in Intestinal Content, Intestinal Mucosa and Blood Plasma

Abstract

ETHYLENEDIAMINETETRAACETIC acid (EDTA) added to a diet containing isolated soybean protein has improved the growth rate and reduced the incidence of a hock disorder caused by zinc deficiency¹ in chickens. Furthermore, the addition of histidine and 8 ml. anti-arthritic agents, including acetylsalicylic acid (aspirin), prevented “arthritic-like” leg abnormalities in chickens fed such diets deficient in zinc^2,3. Supplementation of the diet with zinc promoted normal growth and feather development, and prevented leg abnormalities, while supplementation with the anti-arthritic agents had little or no effect on the symptoms of zinc deficiency except the leg defect. Amino-acids, particularly histidine, seem to be involved in the passage of zinc from the intestinal lumen to the blood stream^4,5. EDTA was found to bind zinc in the intestinal digesta and seemed to remain bound as it passed through the intestinal mucosa and was transported in the blood plasma, confirming previous work⁵. We have investigated the binding of histidine and aspirin to zinc and their transport from intestinal digesta to the blood stream to find out whether these compounds alleviate the abnormal leg conditions by the same mechanism.