title: Stress affects a gastrin-releasing peptide system in the spinal cord that mediates sexual function: implications for psychogenic erectile dysfunction.
abstract: BACKGROUND
  Many men suffering from stress, including post-traumatic stress disorder (PTSD), report sexual dysfunction, which is traditionally treated via psychological counseling. Recently, we identified a gastrin-releasing peptide (GRP) system in the lumbar spinal cord that is a primary mediator for male reproductive functions.
  
  
  RESULTS
  To ask whether an acute severe stress could alter the male specific GRP system, we used a single-prolonged stress (SPS), a putative rat model for PTSD in the present study. Exposure of SPS to male rats decreases both the local content and axonal distribution of GRP in the lower lumbar spinal cord and results in an attenuation of penile reflexes in vivo. Remarkably, pharmacological stimulation of GRP receptors restores penile reflexes in SPS-exposed males, and induces spontaneous ejaculation in a dose-dependent manner. Furthermore, although the level of plasma testosterone is normal 7 days after SPS exposure, we found a significant decrease in the expression of androgen receptor protein in this spinal center.
  
  
  CONCLUSIONS
  We conclude that the spinal GRP system appears to be a stress-vulnerable center for male reproductive functions, which may provide new insight into a clinical target for the treatment of erectile dysfunction triggered by stress and psychiatric disorders.
authors.affiliation: Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kyoto, Japan. hsakamo@koto.kpu-m.ac.jp
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Sakamoto
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Matsuda
authors.forename: Damian G
authors.initials: DG
authors.lastname: Zuloaga
authors.forename: Nobuko
authors.initials: N
authors.lastname: Nishiura
authors.forename: Keiko
authors.initials: K
authors.lastname: Takanami
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Jordan
authors.forename: S Marc
authors.initials: SM
authors.lastname: Breedlove
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kawata
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004542:Ejaculation; D007172:Erectile Dysfunction / Q000378:metabolism*; D019886:Gastrin-Releasing Peptide / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011944:Receptors, Androgen / Q000378:metabolism; D020018:Sexual Dysfunctions, Psychological / Q000378:metabolism*; D013116:Spinal Cord / Q000378:metabolism*; D013313:Stress Disorders, Post-Traumatic / Q000150:complications; D013315:Stress, Psychological; D013739:Testosterone / Q000097:blood
chemical_list: D011944:Receptors, Androgen; D013739:Testosterone; D019886:Gastrin-Releasing Peptide