Antagonism of Growth and Sex Hormones of the Anterior Hypophysis

That the anterior lobe of the mammalian hypophysis liberates a hormone stimulating growth and essential for growth to normal stature would seem abundantly proved both by the work in the experimental production of gigantism1and in experimental hypophysectomy2accomplished during the last few years in this laboratory. We have also taken the important initial steps to secure the growth hormone in a sterile, easily absorbable and almost protein-free solution, steps which to some extent have been made the basis of recent communications from other laboratories.3 About two years ago Zondek and Aschheim4and P. E. Smith,5working independently, secured a totally distinct effect from the implantation of anterior hypophyseal substance—the induction of precocious sexual maturity in young mammals, mice and rats. The vaginal smear and behavior changes showed clearly that estrus had been induced. Examination of the young animals after they had been killed showed