Spinal trigeminal nucleus (Sp5)

The Spinal trigeminal nucleus is a large sensory nucleus in the brainstem that receives primary afferent fibers from the trigeminal nerve (Cranial Nerve V) (StatPearls, 2023). It is functionally divided into three subnuclei: pars oralis, pars interpolaris, and pars caudalis, with the pars caudalis being the primary site for processing pain and temperature information from the face and head (NIH, 2022). This region serves as a critical relay station in the trigeminovascular system, making it a focal point for the pathophysiology of primary headaches like migraine and neuropathic conditions like trigeminal neuralgia (PubMed, 2021). While not a single molecular target itself, it contains numerous receptors (e.g., CGRP receptors, 5-HT1B/1D receptors) and ion channels that are targeted by analgesics and anti-migraine medications (Journal of Headache and Pain, 2020). Therapeutic intervention in this area aims to dampen the hyperexcitability of second-order neurons to alleviate chronic or acute craniofacial pain.

Other names

Trigeminal spinal nucleusSpinal nucleus of the trigeminal nerveNucleus spinalis nervi trigeminiSpinal trigeminal nucleus

Modulation of neurotransmission (e.g., inhibition of CGRP release or blockade of voltage-gated sodium channels) within the brainstem to reduce nociceptive signaling from the trigeminal nerve.