抄録
The effects of early postnatal administration of estrogen on the development of the hypothalamic regulatory mechanism of the pituitary gonadotrophic function were different according to doses of estrogen and lengths of the injection period.Daily injections of small doses for short periods resulted in the persistent-estrous state, while after prolonged treatment with large doses, the hypothalamus was more severely affected resulting in the persistent-diestrous condition. If animals were given a treatment with estrogen of medium grade, reactions may vary among different individuals, persistent-estrous, persistent-diestrous and irregularly cyclic rats being produced.
