Trigeminal sensory neuron (TSN) (TSN)

Trigeminal sensory neurons are the primary afferent cells of the trigeminal nerve (Cranial Nerve V), responsible for transmitting sensory information from the face, scalp, and intracranial structures to the central nervous system (StatPearls, 2023). These neurons are highly specialized, with cell bodies located in the trigeminal ganglion and axons that project to the trigeminal nucleus caudalis in the brainstem (PubMed, 2021). They are central to the pathophysiology of migraine, where activation of trigeminovascular fibers leads to the release of vasoactive neuropeptides like Calcitonin Gene-Related Peptide (CGRP) and Substance P (Nature Reviews Neurology, 2018). Pharmacological intervention often focuses on the receptors expressed by these neurons, such as serotonin 5-HT1B/1D receptors and CGRP receptors, to inhibit pain signaling and neurogenic inflammation (Journal of Headache and Pain, 2020). While these neurons are a critical anatomical site for therapy, they represent a cellular population rather than a single molecular target.

Other names

Trigeminal ganglion neuronTrigeminal primary afferentCranial nerve V sensory neuronTrigeminal nociceptor

Drugs targeting the trigeminal system typically act by modulating the activity of specific receptors and ion channels located on these neurons. For instance, triptans act as agonists at 5-HT1B/1D receptors to inhibit neuropeptide release and cause vasoconstriction, while gepants and monoclonal antibodies target the CGRP pathway to prevent neurogenic inflammation and pain transmission (Nature Reviews Neurology, 2018). Other agents, such as local anesthetics and certain anticonvulsants, inhibit voltage-gated sodium channels to reduce neuronal excitability and ectopic firing (StatPearls, 2023).