Quantitative Studies of Prostatic Secretion* I. Characteristics of the Normal Secretion; the Influence 0~ Thyroid, Suprarenal, and Testis Extirpation and Androgen Substitution on the Prostatic Output by Charles

A simple surgical procedure was devised enabling frequent collection of prostatic secretion over long periods of time in dogs. The serial observations of secretion so obtained permitted assay of the physiological work of the prostate, since this gland has no known endocrine function. Reactions of the canine prostate are of special interest because the dog is the only laboratory animal which develops spontaneous prostatic hypertrophy similar to that in man (1). I t is well known that the mature prostate gland is not a self-contained functional unit but directly depends for its maintenance on testis secretion, which in turn is greatly influenced by other endocrine products. While interest was centered in the amounts and quality of secretion as indices of prostatic activity, these values reflected in turn the more general factors influencing the genital complex as a whole and the activity levels of this functional system were accordingly repeatedly determined. In this paper quantitative data are presented on the prostatic secretion of normal dogs; on the rate of atrophy of the prostate after castration, and the restoration of secretion by injections of male sex hormones in castrate dogs; on the influence of hyperthyroidism and thyroid and suprarenal removal on the prostate; and on the chemical composition of prostatic fluid in these various states. The influence of confinement on the canine testis is also reported.