RESPONSES OF NORMAL AND HYPOPHYSECTOMIZED IMMATURE RATS TO MENOPAUSE URINE INJECTIONS

Abstract

A single extract prepared by the method of Levin and Tyndale was used. 164 normal and 77 hypophysectomized rats were injected with menopause urine extract and 130 normals with pregnancy urine extract. The dosage levels at which luteiniza-tion appeared and the relationship of ovarian and general body size to luteinization was detd. In the normal animals the dosage which induced luteinization showed great variability; in the hypophysectomized rats it was quite uniform. There appeared to be no correlation between body size and the ovarian response. Luteinization appears to be a function of dosage and is not accompanied by a sufficient ovarian increase to reveal the change in dosage. The validity of quantitative assays of the relative amounts of urinary FSH and LH when made on normal rats are evidently of questionable validity. Whether an extract gives a response similar to menopause or to pregnancy urine can be satisfactorily detd.