It was found that oxytocin, a "maternal hormone" synthesized in the brain, acts on the spinal cord far away from the brain via a new local neural mechanism'volume transmission'and promotes male mating behavior at the spinal cord level. ..An international research group from Okayama University, Kanagawa University, Kawasaki Medical School, Toyama University, National Institute of Genetics, Emory University in the United States, and Oxford University in the United Kingdom has revealed.
It is known that the sexual function center that regulates male sexual functions such as erection and ejaculation exists in the spinal cord, but it has not been known how it is controlled by the brain.In this study, administration of oxytocin, a neuropeptide hormone deeply involved in maternity, to the spinal cord of male rats activates the sexual function center, and conversely, administration of a blocker of oxytocin inhibits the action of oxytocin in the spinal cord. He found that ejaculatory ability diminished and revealed that oxytocin regulates male sexual function centers.
Furthermore, the action of oxytocin in the spinal cord is not'wiring transmission'through synaptic connections between neurons, but oxytocin neurons in the brain extend axons to the distant spinal cord and release oxytocin locally. We also found that it was mediated by a novel intraspinal local neural mechanism'volume transmission'that diffused.If wiring transmission by synapse is'Ethernet' represented by wired LAN (local area network), volume transmission is a system similar to'Wi-Fi'.
This achievement, which clarified the mechanism of operation of the brain-spinal network that controls male sexual function, may lead to the development of a fundamental treatment for psychogenic sexual dysfunction in humans in the future.
Paper information:[Current Biology] Oxytocin influences male sexual activity via non-synaptic axonal release in the spinal cord