75Se-selenomethionine excretion in bile and pancreatic juice.

The radioactivity in the bile and pancreatic juice of two patients was measured after intravenous injection of 75Se-l-selenomethionine. The concentration of radioactivity in both fluids is almost equal. Thin-layer chromatography shows that the main part of radioactivity in pancreatic juice is due to unbound 75Se-selenomethionine, while free 75Se-selenomethionine is only a minor part of the total radioactivity appearing in the bile.