Abstract
To elucidate the role of fat-soluble vitamins and female sex hormones on motility of uterine muscle, their effects upon actomyosin-ATPase (E.C. 3. 6. 1. 3.) of rabbit's uterine muscle was investigated. Crude uterine actomyosin was extracted by the method of Szent-Gyorgyi from albino rabbits after administration of the vitamins and hormones and the enzymic activities were determined. The results are as follows : 1) The enzymic activity of crude uterine actomyosin of rabbit was not affected by vitamins A and E. 2) Vitamins D and K accelerated the actomyosin activity and it was more manifest by the combined use of these drugs and estrogen. But progesterone did not facilitate the activity in combined use. 3) The enzymic activity of crude uterine actomyosin was promoted by estrogen, but it was not affected by progesterone.
