Progesterone in the blood. A quantitative method employing gas liquid chromatography

Simple and rapid method for the determination of progesterone in rat plasma by gas-liquid chromatography with electron-capture detection

A method for estimating progesterone in rat plasma using gas-liquid chromatography (GLC) with electron-capture detection is described. By means of a column chromatographic technique for the extraction of progesterone from plasma, it is possible to isolate the steroid in such a specific way that, contrary to previously published methods, no additional chromatographic purification and separation steps are needed prior to the final GLC analysis. As a derivative for electron-capture detection we used the 3,20-di-O-pentafluorobenzyloxime of progesterone. This derivative is superior to those used hitherto with regard to sensitivity and stability. The high overall recovery (mean value, 89.4%) makes this method especially convenient for research work when only little plasma is available, or when the concentration of progesterone is very low.

The influence of progesterone on the antidiuretic and oxytocic activities of the posterior pituitary lobe of female rats

Mature, female rats received 2 mg progesterone i.m. during proestrus and estrus and 4 mg during all stages of the sexual cycle. 24 h after injection the animals were decapitated. Antidiuretic and oxytocic activities of the posterior pituitary lobe were tested by bioassay. The increased hormone content of the neurohypophysis in reaction to progesterone administration is explained by an inhibiting effect of progesterone on hormone secretion. The physiological and possible pathophysiological importance of this effect is discussed, expecially with regard to the genesis of cyclic edema and late pregnancy gestosis.