Diethyldithiocarbamateによる射精の抑制効果ならびに副性腺内モノアミンの変動について

Abstract

Effects of diethyldithiocarbamate(DDC) on erection and ejaculation were investigated and monoamine levels in central nervous system, gonad and accessory glands were determined in dogs. Intraperitoneal administration of 50, 75 and 100 mg/kg of DDC suppressed ejaculation 1 hour after administration, although penial erection did occur. This suppression of ejaculation was recovered to some extent 3 hours after DDC and completely recovered 24 hours after DDC. One hour after the administration of 100 mg/kg of DDC, noradrenaline (NA) level in the caudate and serotonin (5-HT) level in the posterior hypothalamus decreased significantly, as compared with the control. However, there were no significant changes in the regions of anterior hypothalamus and hippocampus which are known to play an important role in sexual behavior. In the epididymis, NA and adrenaline levels decreased significantly, though 5-HT levels increased, as compared with those of the control. In the prostate and posterior urethra, NA levels decreased significantly, as compared with the control. The seminal emission induced by hypogastric nerve stimulation induced a gradual rise in the posterior urethral pressure. When the pressure reached the maximum level, rhythmic alterations of the pressure considered to be a phenomenon associated with ejaculation occurred. DDC (100 mg/kg) abolished both seminal emission and rhythmic alterations of the posterior urethral pressure. These findings indicate that the sperm transport may be inhibited by decrease of NA level in accessory glands.