Title:Serotonergic 5-HT7 Receptors as Modulators of the Nociceptive System
Volume: 21
Issue: 7
Author(s): Rita Bardoni*
Affiliation:
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena, and Reggio Emilia, Modena,
Italy
Keywords:
Serotonin, pain, 5-HT7 receptors, spinal cord, brain, synaptic transmission, endogenous analgesia.
Abstract: The biogenic amine serotonin modulates pain perception by activating several types of serotonergic
receptors, including the 5-HT7 type. These receptors are widely expressed along the pain axis,
both peripherally, on primary nociceptors, and centrally, in the spinal cord and the brain. The role of
5-HT7 receptors in modulating pain has been explored in vivo in different models of inflammatory and
neuropathic pain. While most studies have reported an antinociceptive effect of 5-HT7 receptor activation,
some authors have suggested a pronociceptive action. Differences in pain models, animal species
and gender, receptor types, agonists, and route of administration could explain these discrepancies. In
this mini-review, some of the main findings concerning the function of 5-HT7 receptors in the pain
system have been presented. The expression patterns of the receptors at the different levels of the pain
axis, along with the cellular mechanisms involved in their activity, have been described. Alterations in
receptor expression and/or function in different pain models and the role of 5-HT7 receptors in controlling
pain transmission have also been discussed. Finally, some of the future perspectives in this field
have been outlined.