Effect of Testosterone and Progesterone on the Adrenal X-Zone in Female Mice

Abstract

In order to extend studies on roles of androgen and progesterone in the degeneration of the X-zone, 30-day-old ICR female mice were used. The X-zone was degenerated by 6-days' treatment with progesterone as well as with testosterone. Testosterone had strong effects on the X-zone, leading to its complete disappearance at any daily dose of 2.5, 1.0, 0.5 and 0.1 mg. Progesterone had less effects; the X-zone disappeared in 8 of 9 mice daily given 2.5 mg, and in only one of 6 mice daily given 1.0 mg; the X-zone remained unchanged in all mice daily given 0.5 mg in many cases. Degenerative changes of the X-zone callsed by testosterone differed from those caused by progesterone in such a way that the testosterone-induced degeneration was followed by a gradual juxta-medullary fibrous replacement while the progesterone-induced degeneration appeared fatty in nature. Due to some exceptions in which, testosterone induced fatty degeneration and progesterone induced fibrous replacement, the differences mentioned above was not strictly specific. To eliminate endogenous hormones from the ovary and conversion of progesterone to androgen in the gland, some mice were ovariectomized and given 2.5 mg progesterone. As a result, the X-zone was relatively well maintained. This means that progesterone does not exert any destructive effect directly on the X-zone, but does so via the ovary, in which progesterone may be converted in part into testosterone.