THE AMERICAN JOURNAL OF ANATOMY 165:13-25 (1982) Morphometric Studies on Rat Seminiferous Tubules

The goal of this morphometric study was to obtain quantitative information on the seminiferous tubules of Sprague-Dawley rats, including changes seen at various stages of the cycle of the seminiferous epithelium. Tissue from perfusion-fixed testes was embedded in Epon-Araldite; and sections were subjected to morphometric measurements at the light microscopic level, using point counting for volume densities and the Floderus equation for numerical densities. Changes occur in the diameter of the seminiferous tubule, as well as in the volume of the seminiferous epithelium and tubule lumen, from stage to stage during the cycle. A significant constriction of the seminiferous tubule accompanies spermiation. The volume of the seminiferous epithelium per unit length of the tubule begins to increase after stage XIV, and peaks at stage V of the next cycle. The tubule lumen increases dramatically from stages V to VII, at the expense of the