Experiences of animal experiments with tritiated Oradexon

50 μCi 1.2(n)-3H labelled dexamethason was given to pregnant sheep 24, 36 or 48 hours before the planned artificial abortion. Caesarean section was performed on the 120. day of pregnancy and the radioactivity of the different organs of the premature sheep was determined. The steroid administered to the mother appeared rapidly in the foetus. 24 hours after the injection 3/4 of the total activity was found in the kidneys and in the liver. The radioactivity of the lungs increased as a function of time, and 12 hours later a parallel increase of the level of lecithin+surfactant was observed, too. It is suggested that the lecithin-synthesis is stimulated by the steroid by means of enzyme-induction. The increasing radioactivity of the amniotic fluid originates from the foetal kidneys. (author)