Cervicogenic headache is a syndrome characterized by chronic hemicranial pain that is referred to the head from either bony structures or soft tissues of the neck. The trigeminocervical nucleus is a region of the upper cervical spinal cord where sensory nerve fibers in the descending tract of the trigeminal nerve (trigeminal nucleus caudalis) are believed to interact with sensory fibers from th...

This study aimed to assess the effect of intra-habenular injection of morphine on acute trigeminal pain in rats. Also here, we examined the involvement of raphe nucleus opioid and 5HT3 receptors on the antinociceptive activity of intra habenular morphine to explore the possibility of existence of descending antinociceptive relay between the habenula and raphe nucleus. The numbers of eye wiping ...

It has been recently shown in rats that spontaneous movements of whisker pad macrovibrissae elicited evoked responses in the trigeminal mesencephalic nucleus (Me5). In the present study, electrophysiological and neuroanatomical experiments were performed in anesthetized rats to evaluate whether, besides the whisker displacement per se, the Me5 neurons are also involved in encoding the kinematic...

Interactions between somatosensory and auditory systems occur at peripheral levels in the central nervous system. The cochlear nucleus (CN) receives innervation from trigeminal sensory structures: the ophthalmic division of the trigeminal ganglion and the caudal and interpolar regions of the spinal trigeminal nucleus (Sp5I and Sp5C). These projections terminate primarily in the granule cell dom...

We investigated the hypothesis that the motor trigeminal nucleus, consisting of expiratory motoneurons, might be influential in termination of inspiration. We addressed the issue by comparing the effects on neural respiration of a reversible, unilateral, pharmacologic blockade of the motor trigeminal nucleus (5M), the medial parabrachial nucleus (PB), and of other nearby structures that are neu...

Apnea is an important protective response to upper airway irritation, but the central mechanisms responsible for eliciting sensory-induced apnea are not well understood. Recent studies have emphasized the Kölliker-Fuse nucleus in producing apnea and proposed a trigeminoparabrachial pathway for mediating these reflexes. However, in our earlier study of apneic responses produced by glutamate stim...

Trigeminal neuralgia (TN), also known as tic douloureux, is a pain syndrome recognizable by patient history alone. The condition is characterized by intermittent unilateral facial pain. The pain follows the unilateral (>95%) sensory distribution of trigeminal nerve (V), typically radiating to the maxillary (V2) or mandibular (V3) area. Ophthalmic division (V1) pain alone occurs in <5% patients....

The trigeminal pain pathway, as related to migraine, is represented by three main sites: i) the trigeminal nerve and ganglion providing unmyelinated C fibers that innervate the vessels (the trigeminovascular system) and the central projections to the brainstem; ii) the trigeminal nucleus caudalis (TNC) in the brainstem; and iii) the brain as the site of pain consciousness. Each of these sites h...

By means of retrograde axonal transport of horseradish peroxidase (HRP), the distribution of trigeminotectal neurons of the cat has been studied in some detail (Baleydier and Mauguiere, 1978 ; Nagata and Kruger, 1979 ; Ogasawara, 1981). These studies have indicated that the intermediate and deep layers of the entire superior colliculus (SC) receive fibers from the contralateral sensory trigemin...

The primary (S1) and secondary (S2) somatosensory cortices project to several trigeminal sensory nuclei. One putative function of these corticofugal projections is the gating of sensory transmission through the trigeminal principal nucleus (Pr5), and some have proposed that S1 and S2 project differentially to the spinal trigeminal subnuclei, which have inhibitory circuits that could inhibit or ...