Spinal 5-HT1A Receptor Plays A Major Role In Directing Serotonergic Modulation Toward Inhibition On Mechanical Allodynia Of Carrageenan Inflammation | 53865
ISSN: 2167-0846

Journal of Pain & Relief
Open Access

Our Group organises 3000+ Global Conferenceseries Events every year across USA, Europe & Asia with support from 1000 more scientific Societies and Publishes 700+ Open Access Journals which contains over 50000 eminent personalities, reputed scientists as editorial board members.

Open Access Journals gaining more Readers and Citations
700 Journals and 15,000,000 Readers Each Journal is getting 25,000+ Readers

This Readership is 10 times more when compared to other Subscription Journals (Source: Google Analytics)

Spinal 5-HT1A receptor plays a major role in directing serotonergic modulation toward inhibition on mechanical allodynia of carrageenan inflammation

International Conference on Pain Research & Management

Jeong Il Choi

Chonnam National University, South Korea

Posters & Accepted Abstracts: J Pain Relief

DOI: 10.4172/2167-0846.C1.012

Introduction: Descending serotonergic projections may facilitate or inhibit nociceptive processing in the spinal cord depending on several factors. Unlike other pain states, spinal 5-hydroxytryptamine 3 receptors (5-HT3R) were shown to play a limited role in nociceptive transmission of carrageenan-induced inflammatory pain. Instead, a facilitatory role of 5-HT1AR and 5-HT1BR in spinal nociceptive processing was observed during early-phase of carrageenan model. Although, the maximum release of 5-HT in spinal cord reaches the maximum 2-3 hours after carrageenan injection (early-phase), its release returns to baseline 8 hours. Aim: To identify the role of Spinal 5-HT1A receptor in directing serotonergic modulation toward inhibition on mechanical allodynia of carrageenan inflammation. Methods: Effects of intrathecal (i.t.) nonspecific 5-HTR agonist, subtype agonist or antagonists (5-HT1AR, 5-HT1BR, 5-HT3R), and 5,7-dihydroxytryptamine (5,7-DHT, a serotonergic neurotoxin) on mechanical allodynia were tested for earlyand late-phase allodynia. Results: Lesioning spinal serotonergic projections with 5,7-DHT induced a significant increase in the intensity of mechanical allodynia at both early and late-phase. This increase was attenuated by i.t. 5-HT. Also, i.t. 5-HT itself produced a significant antiallodynic effect in late-phase, but not in early-phase. Similarly, i.t. 5-HT1AR agonist (8-OH-DPAT) attenuated the intensity of late-phase allodynia in a dose-dependent manner which was antagonized by 5-HT1AR antagonist (WAY-100635), but produced no effect on the early-phase allodynia. However, other agonists or antagonists of 5-HT1BR and 5-HT3R did not produce any anti or pro-allodynic effects. Conclusion: Descending serotonergic modulation plays a vital role in inhibition of nociceptive processing during late-phase allodynia, which involves spinal 5-HT1A, but not 5-HT1B or 5-HT3 receptors in carrageenan-induced inflammation. However, the defined role of 5-HT1A and serotonergic inhibition during early-phase remains undetermined.

Email: [email protected]