Effects of Orchiectomy on the Adrenal Zona Reticularis of Adult Rats: An Ultrastructural Morphometric Study

Abstract

The effects of orchiectomy on the fine structure of the zona reticularis of sexually mature adult rats were investigated morphometrically at 1,2,3,4and 8 weeks after castration. The average thickness of the reticularis zone showed a significant increase at 8 weeks. The average surface areas of the sections through the entire cell and all its mitochondria or lipid droplets per reticularis cell section increased rapidly and reached an initial peak at 2 weeks. Thereafter, they decreased at 3 weeks, and then the average sectional areas of both the entire cell and the lipid droplets reached a second peak at 4 weeks, while that of the mitochondria continued to increase gradually. A similar tendency was also demonstrated in the percentage area of the cytoplasm occupied by lipid droplets or by mitochondria. On the other hand, the average sectional area of the nucleus remained almost unchanged between postcastration weeks 1 and 4, but increased signficantly at 8 weeks.
These data appear to be associated with hypertrophy and proliferation of the reticularis cells, and may therefore suggest that the zona reticularis in sexually mature rats can be activated to compensate for a deficiency of testosterone induced by orchiectomy.