Seminal emission by electrical stimulation of the spermatic nerve and epididymis

The spermatic nerve and epididymis were stimulated electrically in dogs to elucidate the possibility of artificial seminal emission after bilateral transection of the hypogastric nerves and sympathetic trunks. Before transection, electrical stimulation of a distal end of the severed spermatic nerve caused a trace amount of emission in two dogs and no emission in the remaining four. In contrast, 1 month after the transection, stimulation of a distal end of the severed spermatic nerve caused seminal emission in all six dogs examined, with full seminal volume in four dogs and partial volume in the remaining two. Anatomically, sympathetic nerves originating from the upper portion of the lumbar sympathetic ganglia descended along the spermatic arteries to the testes as spermatic nerves. The present results indicate that spermatic nerves have the potential to generate seminal emission as a compensatory pathway after bilateral transection of the hypogastric nerves. Both direct and percutaneous electrical stimulation of epididymal tails resulted in a full volume of seminal emission in all dogs with transection of both hypogastric nerves and lumbosacral sympathetic trunks as well as in unoperated controls, while high voltage (8 V vs 40-80 V) was required to cause seminal emission by electrical stimulation on the skin surface. Direct stimulation of epididymal tails in men undergoing orchidectomy as treatment for prostatic carcinoma or during biopsy of the contralateral testis in a patient with a testicular tumour, resulted in seminal emission in all five epididymides examined either from the end of the severed vas deferens or in the posterior urethra if the vas deferens was not severed.