Untersuchungen über das genitale Altern des Rattenweibchens

Abstract

The reproductive life of the female rat involves the juvenile period (about 3 months), the period of fertility (about 12 months) and a long postreproductive period (about 21 months). The latter period consists of a phase of persistent estrus (hyperfolliculinism and/or hypoluteinism) of 1 to 1 1/2 years, a period of diestrus (hyperluteinism and/or hypofolliculinism) and a short period of senility. The persistent estrus and the diestrus are phases of functional hormonal imbalance which does not mean the cessation of the endocrine activity of the pituitary and the ovaries. Not before the short period of senility does this activity cease and the genital organs show morphological involution. The hormonal imbalance is due to the disturbance of pituitary stimulation. The ovaries, during the whole period, continue to produce young follicles which, however, do not attain maturity.