ANDROGENS IN TESTICULAR VENOUS BLOOD IN THE ADULT RAT

Abstract
A simple method for the collection of pure testicular venous blood (TV-blood) in the rat is presented. Exposing the testicle on the abdomen, a cannula made of fine polyethylene tube is inserted through the tunica albuginea into one of longest branches of the testicular vein. In this manner usually more than 5 ml of TV-blood could be collected in the 3-4 hours before its flow ceased. Testosterone and androstenedione were measured both in TV-blood and in the testis, using 88 adult rats with and without HCG pretreat-ment. Testosterone was the major androgen elaborated by the adult rat testis. Following a short treatment with HCG, the level of testosterone in TV-blood (ca. 3 [mu]/100 ml whole blood) was elevated about 8 times and the concentration in the testis (ca. 10 [mu]/100g wet weight) was doubled. After stimulation with HCG, androstenedione increasedto a detectable level in both TV-blood and the testis.