ON THE PROLONGED INFLUENCE OF GONADAL HORMONES AND OF A DIET WITH A HIGH CA/P-RATIO ON BONE IN THE RAT
ABSTRACT Young ovariectomized female albino rats were treated with gonadal hormones (oestrogen, androgen and progesterone) for half a year, during which time they also received a diet with a high Ca/P-ratio and sugar. The effect of this treatment on the body weight and the weight, length, and Ca-, P-, and N-content of the femurs was investigated. The weight of the femurs given in percentage of the mean initial body weight was significantly lowest in the oestrogen group and highest in the androgen group. The significantly lowest Ca content was observed in the androgen group and also in the progesterone group. In the oestrogen group the value was no higher than that in the control series. The phosphorus content of the femurs was higher for the animals which had undergone hormonal treatment than for the control animals. The N-content in the androgen and progesterone groups, but not in the oestrogen group, was significantly lower as compared with the controls. It seems likely that a diet with a high Ca/P-ratio, which contains more carbohydrates than an ordinary diet, would not be unfavourable for the calcification of developing bone with regard to the Ca-, P- and N-contents of the bone. Of the gonadal hormones androgen particularly, and to some extent progesterone seem to have a reducing effect on the Ca- and N-contents of the bone under these conditions.