[Fluoride metabolism in the rat. 3. Distribution in the gastrointestinal tract after oral application].

With relation to the investigation of the mechanism of absorption in the gastrointestinal tract, the present third communication deals with a study of the distribution or absorption of fluorine-18 after oral application. This mode of application creates experimental conditions simulating the conditions of water fluoridation. Special attention is paid to the fluorine distribution or absorption in the following six portions: stomach, segments 1--3 of the small intestine, coecum und rectum. Furthermore, the question of its possible accumulation in the soft parts and its retention in the hard tissues were examined as compared with the results from intravenous application.