[Gonadal function of rats following pre- or postnatal administration of some hormones (author's transl)]

Some steroid hormones as well as clomiphene have been administered to new-born rats (postnatally) or to pregnant rats (prenatally) in order to study the effect on the future gonadal function of the animals born before or after the injection. A single postnatal androgen injection in oily solution influences only the female function; estrogen or the combination of androgen and estrogen are effective in both sexes preventing the ovulation or damaging the testicles. If the hormone is administered in water instead of oil, several injections are necessary in order to obtain an effect. Only the aqueous solution of clomiphene produces a positive effect even given in a single injection. When a single postnatal injection is effective the same result can be obtained after prenatal administration but only following intraamniotic injection. Clomiphene is an exception to this rule; intraamniotic injection has no effect. These observations permit the following conclusions: 1. It is possible to influence the hypothalamus-hypophysis function not only in the first days of life but already in the prenatal period. 2. As androgen damages only the ovary, estrogen however the gonads of both sexes, the mechanisme of action can not be the same. Androgen alters the function of the sexual centres in the brain only in the female rat, estrogen paralyses this function in both sexes. 3. Prenatal injection of hormone is only effective if administered intraamniotically (eliminating in this way the action of the placenta). This proves the important role of the placenta in the metabolisme of the hormones. 4. Other possible consequences of postnatal androgen administration as permanent obstruction of the vagina or hypertrophy of the clitoris can be obtained equally by prenatal intraamniotic injection. These phenomena can also occur independent of the avarian processes, being due to direct hormonal action. 5. Tubo-ovarian inflammation and abscesses are observed with relative frequency especially following estrogen or clomiphene-administration. The cause is unknown but we can assume that circulatory disorders in the genital area, produced by the hormone, are responsible for the frequency of these phenomena.