The effect of folliculin and sigetin on the development of the embryo and the placenta in rabbits with normal and impaired sympathetic innervation of the uterus

Abstract

The following conditions of embryos and placentas of rabbits were studied on the twelfth day of pregnancy: their sizes, wet and dry weight of the conceptuses (embryo with yolk sac and amnion) and their hemoglobin content, survival time of embryos in anoxic conditions, and development of the placenta and its filling with maternal and fetal blood. Comparisons were made of the values obtained in the 6 groups of intact female laboratory animals: (1) controls, (2) animals given an intramuscular injection of 25 I.U. of folliculin (estrone), and (3) animals given an intravenous injection of 40 mg. of sigetin (a synthetic preparation of the estrogen type); also comparisons were made of values from similar groups of animals with surgically impaired sympathetic innervation of the uterus. Folliculin and sigetin caused hyperemia of the maternal part of the placenta and hydration of the conceptus and an increase in its hemoglobin content. In the operated animals, folliculin exerted an unfavorable influence on embryogenesis. After the injection of sigetin into these animals, the condition of the embryos, which deteriorated after the operation, improved, and approached normal in spite of the hydration of the conceptuses. The mechanisms of the two preparations influencing the condition of embryos and placentas are discussed.