The influence of peat extract on the seminiferous epithelium of mouse testes.

Because of the interest in the peat extract as a potential therapeutic agent, its effect on the seminiferous epithelium cells was studied. Adult male mice were intraperitoneally injected with peat extract during 34 days. At intervals equal to the duration of the cycle of the seminiferous epithelium (every 8.

Renewal of type A spermatogonia in adult rats.

The origin of type A spermatogonia in the rat, formed at each cycle of the seminiferous epithelium, has been investigated in segments of tubules dissected from the testes of animals killed at 1 and 44 hr after a single injection of [3H]thymidine. After fixation and staining these tubular segments were radioautographed according to the technique of Huckins & Kopriwa (1969). Labelled and unlabelled type A0, A4, A1 and intermediate spermatogonia were mapped and scored in tubular segments at stages I-IV of the cycle of the seminiferous epithelium, i.