The Luteinizing Substance of Pregnancy Urine.

Abstract

That pregnancy urine contains a luteinizing substance was first shown by Zondek. 1 From his later work 2 it appears that the luteinizing substance is different from the agent that causes ripening of the follicles, even though such a separation has not been made with urines of pregnancy.

Extracts prepared by us from pregnancy urine seem to produce both maturation of follicles and luteinization. In the immature mouse or rat premature estrus is effected by their administration. We have tentatively defined one mouse unit as the minimum amount that causes opening of the vagina and estrus on the twenty-second to twenty-fourth day of age, after being administered subcutaneously to 19-day-old mice in 6 equal portions during the course of 3 days. This criterion of activity seems to be quite satisfactory if one is assured of the absence of the estrogenic substances. Depending upon the degree of purification, the mouse unit has varied from 0.03 to 0.001 mgm. This amount produces a marked hyperemia and development of the ovaries and uterus but very little luteinization.

The daily administration of these extracts to adult female rats produces for the first 5 to 10 days an almost continuous state of estrus, due probably to stimulation of the follicular apparatus. Cornified cells then disappear from the smears, possibly as an effect of the extensive luteinization. The inhibition of estrus persists for 5 to 12 days following the cessation of the injections, the cycles then reappearing with a slight prolongation of the diestrus interval. The ovaries of the treated animals are loaded with corpora lutea and weigh 4 or 5 times as much as those of the controls.

Kelly 3 reported that the injection of pregnancy urine into pregnant guinea pigs invariably produces abortion.