by Hiroyuki Oshima, Japan
The neuroendocrine regulatory mechanism modulating the ejaculatory system was the theme of Dr. Oshima's lecture. Dr. Oshima, using the dog as an experimental model, postulated that there exist two mechanisms to control the ejaculatory process: a direct innervation system to the seminal tract with multiple crossing sites, and another involving the humoral system consisting of the greater splanchnic nerve and the adrenal medulla. While elaborating the intricate ejaculatory process, Dr. Oshima demonstrated that electrical stimulation to the lumbar splanchnic nerve elevated intraluminal pressure of the vas deferens and bladder neck and caused contraction of the prostate. Dr. Oshima correlated his experimental studies with clinical ejaculatory disorders. The studies support the presence of two kinds of spinal centers controlling ejaculation. The report clarifies the laterality of the direct sympathetic innervation system from the lumbar spinal cord and provides evidence for a second mechanism from the thoracic spinal cord working through the greater splanchnic nerve causing catecholamine release from the adrenal medulla.
Julian Frick, Austria Neuroendocrinology of Sexual Reaction