Selenium proteins in ovine tissues: III distribution of selenium and glutathione peroxidases in tissue cytosols

✍ Scribed by R.S. Black; M.J. Tripp; P.D. Whanger; P.H. Weswig

• Publisher: Elsevier Science
• Year: 1978
• Weight: 715 KB
• Volume: 8
• Category: Article
• ISSN: 0006-3061
• DOI: 10.1016/s0006-3061(00)80241-0

✦ Synopsis

Three 6 week-oId lambs were injected with carrier-free selenium-75 as sodium selenite initially and again after 6 days. One lamb received no further injections whereas the other two received injections of either vitamin E-or unlabeled Na@eOa when the fK.st selenium-75 injection was given. Selected tissues were removed at autopsy 10 days after the fast injection. The cytosol from homogenates of these tissues was subjected to gel chromatography, and the elution profiles determined for radioactivity, protein content, and glutathione peroxidase activity using either hydrogen peroxide or cumene hydroperoxide as substrates. The selenium-75 was found to be distriiuted mainly between 2 different MW peaks. The larger MW seleno-peak (90,000) possessed both glutathione:hydrogen peroxide oxidoreductase, and glutathione:cumene hydroperoxide oxidoreductase activities, but the smaller h%W seleno-peak (about 10,000) possessed no glutathione peroxidase activity. A peak of about 60,000 daltons containing only glutathione:cumene hydroperoxide oxidoreductase activity and no selenium-75 was found primarily in the liver and kidney. Vitamin E had no effect on the elution proffies. Selenium status of the animal had only a minor effect on the selenium-75 dist&ution in the cytosol. but had a marked effect on the absolute amount of label taken up by tissues.