Biology of Reproduction, Vol 13, 269-273, Copyright © 1975 by Society for the Study of Reproduction

The Influence of Androgenization on the Tensile Properties of the Rat Uterus

¹ Departments of Anatomy and General Dentistry Schools of Medicine and Dental Medicine University of Connecticut Health Center Farmington, Connecticut 06032

We have previously found that neonatal androgen treatment (androgenization) increases uterine collagen and inhibits the uterine growth response to estrogen. In order to determine whether increased uterine collagen might act as a partial physical barrier to growth, the tensile properties of uteri from normal diestrous females (NF), from NF treated for 14 days with estradiol, and from androgenized adult female rats (AF) were determined on an Instron Universal Testing Machine. Androgenization significantly increased the ultimate tensile strength of the uterus over that of the normal female but did not alter the total amount of stretch. Injection of estrogen for 14 days increased the load bearing capacity of the uterus of NF over that of untreated NF but not to the level of AF. In addition, estrogen injection significantly increased the total amount of stretch. Our data suggest that the increased rigidity in AF is most probably due to an increase in the number of collagen fibers which may potentially act as a partial physical barrier to uterine growth.