The effects of extracts of the mammalian hypophysis upon immature salamanders

The effect on the reproductive system of ablation and implantation of the anterior hypophysis.

“…In immature amphibia, pituitary implants or the injection of extracts hasten testicular development but have little or no effect on the ovaries in A. tigrinum (Burns, 1930). The same findings in immature axolotls from a sheep-pituitary extract is reported by Burns and Buyse (1931). When pituitary transplants, which take and function, are made in early larval stages, sexual maturity is hastened (Blount, 1930).…”

“…This was secured only when pituitaries of toads were implanted, those of the frog, beef, dog, cavia, rat, opossum, chick and snake being ineffective. Waronzowa and Blacher (1930) and Burns and Buyse (1932) in extensive investigations in larval urodeles of several species and in mature neotenous forms have shown that regressive changes in the gonads take place after hypophysectomy. These changes are more pronounced in the mature specimens than in the immature.…”