Intestinal Transport of Selenium-75 Selenomethionine

See allHide authors and affiliations

Science  13 Apr 1962:
Vol. 136, Issue 3511, pp. 155-156
DOI: 10.1126/science.136.3511.155


When measured simultaneously, selenium-75 selenomethionine accumulated identically with sulfur-35 methionine across everted hamster intestinal sacs in the presence of carrier methionine. The apparent Km for L-methionine transport was 0.8 x 10-3 M, as calculated from the beta emissions of S35-methionine or the gamma emissions of Se75-selenomethionine. Absorption of Se75-selenomethionine from the gastrointestinal tract of man also occurred, with peak blood levels being reached in about 3 hours. Because of the 122-day half-life of selenium-75 and its multiple gamma emissions, Se75-selenomethionine may serve as a tool in evaluating amino-acid absorption.