ON THE RELATIONSHIP BETWEEN TESTICULAR BLOOD FLOW AND SECRETION OF TESTOSTERONE IN ANESTHETIZED DOGS STIMULATED WITH HUMAN CHORIONIC GONADOTROPHIN

Abstract

The concentration of testosterone has been measured in spermatic vein blood from the left testis in 25 anesthetized dogs, stimulated with human chorionic gonadotrophin and infused with arterial blood via the left spermatic artery at different rates. The secretion of testosterone varied with the rate at which arterial blood was infused and at a constant infusion rate of 3.81 ml/min, animals weighing from 19 to 23 kg produced testosterone at a constant rate over 90 minutes. Infusion rates lower than this decreased the secretion of testosterone, and if arterial blood was infused at a rate of 0.76 ml/min for the first 30 minutes of experimentation, the capacity of the infused testis to secrete testosterone in the ensuing 60 minutes was impaired even in animals given large doses of human chorionic gonadotrophin via the left spermatic artery. A relationship between the arterial blood flow to the testis and its ability to secrete testosterone under the influence of human chorionic gonadotrophin is thus established.