UPTAKE OF INTRAVENOUSLY ADMINISTERED PROGESTERONE, PREGNANEDIONE AND PREGNANOLONE BY THE RAT BRAIN

A method has been developed for the detection, isolation and quantitation of progesterone, pregnanolone and pregnanedione in brain tissue of rats receiving pharmacological hypnotic doses of these three substances. Prior to extraction radioactive tracers were added to brain tissue obtained from animals receiving these agents and the brain tissue extracts were purified by paper and thin layer chromatography. The material administered as well as some of the major metabolites were quantitated by gas liquid chromatography, and corrections for losses throughout the entire procedure and up to injection into GLC were based on recovery of added radioactive markers. The possible significance of the conversion of progesterone into hypnotically more potent metabolites is discussed.