Related Experiment Video
Updated: Jul 7, 2026

Ex Vivo Release of Calcitonin Gene-Related Peptide from the Trigeminovascular System in Rodents
Published on: May 16, 2022
Trigeminal nociceptors express prostaglandin receptors
A M Patwardhan1, J Vela, J Farugia
1Department of Endodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
Abstract:
Orofacial inflammation is associated with prostaglandin release and the sensitization of nociceptive receptors such as the transient receptor potential subtype V(1) (TRPV(1)). We hypothesized that certain PGE(2) receptor subtypes (EP1-EP4) are co-expressed with TRPV(1) in trigeminal nociceptors and sensitize responses to a TRPV(1) agonist, capsaicin. Accordingly, combined in situ hybridization was performed with immunohistochemistry on rat trigeminal ganglia. We next evaluated the effects of specific EP2 and EP3 agonists (butaprost and sulprostone) in cultured trigeminal ganglia neurons. The results showed that EP2 and EP3 are expressed in trigeminal neurons (58% and 53% of total neurons, respectively) and are co-expressed in TRPV(1)-positive neurons (64% and 67 % of TRPV(1)-positive neurons, respectively). Moreover, most of the cells expressing EP2 or EP3 mRNA were of small to medium diameter (< 30 microm). The application of butaprost and sulprostone triggered neuropeptide exocytosis, and butaprost sensitized capsaicin responses. Analysis of these data, collectively, supports the hypothesis that prostaglandins regulate trigeminal TRPV(1) nociceptors via activation of the EP2 and EP3 receptors.
Related Concept Videos
Nociception
G-Protein Gated Ion Channels
Sensory organs,...
Mechanically-gated Ion Channels
Opioid Receptors: Overview
Thermosensation
Pain
