Oxytocin and the gastrin-releasing peptide system in the lumbosacral spinal cord

2015 Fiscal Year Final Research Report

• Project/Area Number: 24680039
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Nerve anatomy/Neuropathology
• Research Institution: Okayama University
• Principal Investigator: SAKAMOTO Hirotaka 岡山大学, 自然科学研究科, 准教授 (20363971)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 性機能 / 脳 / 脊髄 / 神経解剖 / 非シナプス的 / ガストリン放出ペプチド / オキシトシン / 神経内分泌

Outline of Final Research Achievements

We previously demonstrated that the gastrin-releasing peptide (GRP) system, located in the lumbosacral spinal cord of rats, controls spinal centers to promote penile reflexes during male copulatory behavior. The identification of a male-specific neural system regulating sexual functions offers new avenues for potential therapeutic approaches to male reproductive dysfunction. A group of oxytocin neurons situated in the parvocellular part of the paraventricular nucleus and projecting to the spinal cord controls penile reflexes. We have found that the axonal distribution of oxytocin in the lumbar spinal cord exhibits a male-dominant sexual dimorphism in rats. Furthermore, oxytocin binding and expression of the specific oxytocin receptor were both observed in the spinal GRP neurons. Thus, oxytocin efferents might regulate male sexual function through a GRP system-mediated mechanism in the spinal cord.

Free Research Field

神経解剖学、神経内分泌学