The Action of Ovary-stimulating Substance of Hu- Man Urine of Pregnancy on Uterine Motility in the Unanesthetized Rabbit

Two to five hours before the occurrence of ovulation in the unanesthetized rabbit, the motility of the uterus profoundly diminishes from a marked type which is characteristic of oestrus, to a state approximating complete quiescence. This happens whether ovulation results from the normal stimulus of coitus or from the intravenous injection of whole human urine of pregnancy (Reynolds and Friedman, 1930a; 1930b). In view of the recent work of Friedman (1932) which shows that either growth of the Graafian follicle or ovulation and subsequent luteinization may be produced in favorable rabbits by grading the dosage of ovary-stimulating substance of pregnancy-urine, it became of interest in the present experiments to determine the changes which take place in uterine motility as a consequence of the administration of such graded, liminal amounts of the urine-substance. In addition, an attempt has been made to determine whether or not a change in moti lity so induced is dependent upon presence of the ovaries or if it can occur in the absence of the tissue of Graafian logically, follicles and thei then, into three r associ groups .ated : the structures. These experiments fall uterine motility assocated with 1, the the