Effect of Injecting Pregnancy-Urine Extracts in Hypophysectomized Rats. I. The Male. ∗

Abstract

The injection of pregnancy urine (P.U.) in normal young rats causes an increase of the interstitial cells of the testes, an enlargement of the accessories and occasional injury to the tubules (Engle 1 ). Collip et al. 2 reported that injections of placental extracts (which he considers physiologically similar to P.U.) in hypophysec-tomized male rats caused a hypertrophy of the interstitial tissue of the testes, prevented atrophy of the accessories, but did not prevent a loss in weight of the testes or degeneration of the tubules. Freud 3 reported that P.U. increased the size of the testes in hypophysectomized rats but gave no structural details.

We have injected several series of hypophysectomized male rats with Antuitrin S (P.U. extract) starting either immediately after hypophysectomy or after a 20-75 day post-operative period. For controls, either one testis was removed before injections were started or littermates were autopsied at that time. Untreated operated littermates were also autopsied at the end of the treatment period.

As evidence for the completeness of the pituitary ablation, we have: (a) daily weighings, (b) skeletal measurements taken at the time of hypophysectomy and autopsy, (c) weights of adrenals and thyroids, (d) serial sections of the pituitary capsule. In no animals included in our data were fragments of definitely recognizable A.P. found.

The injection of Antuitrin S has shown striking effects aside from the enlargement of the accessories and the hypertrophy of the interstitial tissue, in fact, the latter was less than we had anticipated from observations on similarly treated normal animals. There is a definite and pronounced stimulation of the seminiferous tubules. In the postponed injections, the testes approximately doubled their size, an enlargement which is only in part due to the interstitial-tissue hypertrophy.