Biology of Reproduction, Vol 12, 389-392, Copyright © 1975 by Society for the Study of Reproduction

A Local (Nonsystemic) Effect of the Ovary on the Uterus in Rats

¹ Department of Anatomy, Medical College of Ohio at Toledo, P.O. Box 6190, Toledo, Ohio 43614

In rats which were unilaterally ovariectomized one month before, at the beginning of, or on the fifth day of pseudopregnaney, a greater decidual response occurred in uterine horns ipsilateral to the remaining ovary. In rats unilaterally ovariectomized one month before the induction of pseudopregnancy, uterine horn weights differed by about 10 percent, suggesting that in normal animals, more or less 5 percent of the total decidualizing effect is transmitted to each uterine horn via some as yet unidentified local pathway. Further, the two sides of the reproductive tract show functional differences, since left ovariectomy at any time caused significant differences in decidualization of the uterine horns; but right ovariectomy did so only if done one month before pseudopregnancy inductiOn.