Fluorescence-sensitized autoradiography of tissue incorporation of [75Se]selenomethionine

A method was studied for rapid preparation of autoradiographs for tissue slices by impregnation of nuclear emulsion with liquid scintillators PPO and POPOP. Mixing liquid scintillators, especially a hydrophilic dioxane solvent, with emulsion allowed also rapid autoradiographic grain production. The tissue distribution of [75Se]selenomethionine by fluorescence-sensitized autoradiography was observed after iv [75Se]selenomethionine 555 kBq/kg, The number of autoradiographic grains/10μm2 was increased by the scintillator by 5-10 times. The silver grains in the autoradiograms were distributed both in the pancreatic acini and the islets. The acinar cells showed comparatively more grains uptake than the cells of the islets. The incorporation of [75Se]selenomethionine in liver, thyroid gland and bone marrow has also been utilized as an index of tissue protein synthesis.