NADPH-DIAPHORASE IN GLANDULAR CELLS AND NERVES AND ITS RELATION TO ACETYLCHOLINESTERASE-POSITIVE NERVES IN THE MALE REPRODUCTIVE-TRACT OF MAN AND GUINEA-PIG

The presence of NADPH-diaphorase activity and acetylcholinesterase in the testis, epididymis, vas deferens, seminal vesicle, pelvic plexus, prostate and urethra of man and guinea-pig was investigated with the n itro blue NADPH technique and the thiocholine method, respectively. In human material NADPH-diaphorase activity was found in the Leydig cell s, Sertoli cells and the epithelial linings of the rete testis, the ex cretory ducts, seminal vesicle, prostate and urethra. The guinea-pig m aterial showed staining of the Leydig cells and spermatozoa and simila r epithelial staining of the tract as man. Nerves beneath the epitheli um and in the muscle layers of cauda epididymis, vas deferens, seminal vesicle, prostate and urethra were also stained. NADPH-diaphorase-pos itive nerve cells were seen in the pelvic plexus. Some cells also disp layed acetylcholinesterase activity but others showed activity for onl y one of the enzymes or no activity for either enzyme. In the cauda ep ididymis, vas deferens, seminal vesicle, prostate and urethra acetylch olinesterase-positive nerve fibres formed a plexus beneath the secreto ry cells. It is concluded that NADPH-diaphorase, generally accepted as a nitric oxide synthase, is present in glandular cells of the male ge nital tract. The enzyme is also present in nerves, where it is partly co-localized with acetylcholinesterase.