EFFECT OF A NONSTEROIDAL ANTIANDROGEN, FLUTAMIDE ON INTRALUMINAL ACIDIFICATION IN RAT TESTIS AND EPIDIDYMIS

Flutamide, a pure antiandrogen was administered to intact adult male r ats to study the effect of altered availability of hormones on in situ pH, PCO2 and bicarbonate concentration ([HCO3-]) of seminiferous tubu les, proximal caput, middle caput, middle corpus, and proximal cauda e pididymidis. The weights of the epididymis and ventral prostate as wel l as the plasma testosterone level showed antiandrogenic effects of fl utamide. Relative to controls, flutamide elevated significantly in sit u pH in proximal caput, middle caput, middle corpus and proximal cauda epididymidis but not in seminiferous tubules. In situ PCO2 values in the above segments, after flutamide, were indistinguishable from contr ols and from each other but all values remained significantly higher t han systemic arterial blood PCO2. Flutamide treatment did not change t he [HCO3-] in systemic arterial blood or seminiferous tubules but incr eased markedly the values in proximal caput and middle caput. The resu lts of the present studies support the view that luminal acidification in the rat epididymis is under androgen control and may be important for sperm maturation and storage.