Presence of Selenium-75 in Lipoproteins

Abstract

Normal dogs were injected subcutaneously with H2Se75O3 in dilute HCl which contained l mc Se75 (2 mg Se), and male rats were injected with a single dose of H2Se75O3 in dilute HCl containing approximately 0.2 mc of Se75 and 40 mu g Se. The lipoproteins were isolated by ultracentrifugation and electrophoretic analyses were performed. Results show that a small but significant percentage of the total serum protein- bound Se is bound to lipoprotein. Both the alpha and BETA lipoproteins of dog and rat serum bind Se75, with the greatest percentage in the alpha fraction. In the dog, 3.58% of the total serum Se75 is bound to the lipoproteins of which 2.23% of the total serum Se75 is found in the alpha lipoprotein and 0.58% is found in the BETA or alpha -2-lipoprotein. In the rat, 8.83% of the total serum Se75 is bound to lipoproteins, of which 5.74% of the total is found in the alpha lipoprotein and 4.86% is found in the BETA lipoprotein. The significance of Se in serum lipoproteins is discussed.