Title:The Gastrin-Releasing Peptide Receptor (GRPR) in the Spinal Cord as a Novel Pharmacological Target
Volume: 12
Issue: 5
Author(s): Keiko Takanami and Hirotaka Sakamoto
Affiliation:
Keywords:
Chronic pruritus, erectile dysfunction, gastrin-releasing peptide, gastrin-releasing peptide receptor, sexual function,
somatosensory, spinal cord.
Abstract: Gastrin-releasing peptide (GRP) is a mammalian neuropeptide that acts through the G protein-coupled receptor,
GRP receptor (GRPR). Increasing evidence indicates that GRPR-mediated signaling in the central nervous system plays
an important role in many physiological processes in mammals. Additionally, we have recently reported that the GRP
system within the lumbosacral spinal cord not only controls erection but also triggers ejaculation in male rats. This system
of GRP neurons is sexually dimorphic, being prominent in male rats but vestigial or absent in females. It is suggested that
the sexually dimorphic GRP/GRPR system in the lumbosacral spinal cord plays a critical role in the regulation of male
sexual function. In parallel, it has been reported that the somatosensory GRP/GRPR system in the spinal cord contributes
to the regulation of itch specific transmission independently of the pain transmission. Interestingly, these two distinct
functions in the same spinal region are both regulated by the neuropeptide, GRP. In this report, we review findings on
recently identified GRP/GRPR systems in the spinal cord. These GRP/GRPR systems in the spinal cord provide new
insights into pharmacological treatments for psychogenic erectile dysfunction as well as for chronic pruritus.