Nerves glossopharyngeal nerve

The abdominal vagus and sympathetic nerves are the most important afferent inputs involved in vomiting induced by chemotherapy and radiation [31]. The input from vestibular nerves and the cerebellum plays an important role in the motion disease [52]. The afferent inputs from vagal, trigeminal and glossopharyngeal nerves terminate eventually in the nucleus solitarius tract located in the medulla oblongata which has neuronal connections with other medullary areas involved in emesis, for example, area postrema [53]. 

Because of sensory neuropathy, deep pain is often experienced by patients given vincristine. Through involvement of the glossopharyngeal nerve, throat pain may occur, as may deep pain of almost any other area of the body (31,32). Neuropathic changes are not always peripheral. Hallucinations and overall mental status changes, such as depression and/or psychosis, are also rarely reported (31,32). Another CNS effect is the syndrome of inappropriate antidiuretic hormone secretion, which is a well-characterized side effect of vincristine (31,32). 

The metallic sensation arises from stimulation with certain metallic salts, such as silver nitrate, and is also associated with l-octen-3-one (30). Metallic taste sensations may also arise with pathologies of the glossopharyngeal nerve. 

G. Hellekant, V. Danilova, Y. Ninomiya. Primate sense of taste behavioral and single chorda tympani and glossopharyngeal nerve fiber recordings in the rhesus monkey, Macaca mulatto. J Neuropihysial, Tl (2), 978-993, 1997. 

Four cranial nerves subserve the sense of taste, three of these (facial, glossopharyngeal and vagus) innervate taste bud systems (Fig. 1) and one (trigeminal) supplies free nerve ending receptors. Both of these types of receptors respond to chemical stimuli. Only the taste bud systems of the facial and glossopharyngeal nerves have been studied in sufficient detail with many food compounds. 

Geniculate Ganglion (Facial Nerve) GG. Petrosal Ganglion (Glossopharyngeal Nerve) PG... 

Excessive volumes of local anesthetic in a confined space can lead to life-threatening upper airway obstruction. When glossopharyngeal nerve blocks are used for tonsillectomy, children under 15 kg should be given 1 ml or less of 0.25% bupivacaine per tonsil (350). 

Sher MH, Laing Dl, Brands E. Life-threatening upper airway obstruction after glossopharyngeal nerve block possibly due to an inappropriately large dose of bupivacaine Anesth Analg 1998 86(3) 678. 

Taste receptors reside within taste buds on the tongue, the larynx, and the palate. There are four primary taste sensations sour, sweet, bitter, and salty. By mixing these primary taste sensations, the brain can identify many specific tastes (analogous to primary color mixing). Impulses from the taste buds are carried through the facial, glossopharyngeal, and vagus nerves (cranial nerves VII, IX, and X, respectively) to the brain. Taste is modified by the presence of odor, and in the absence of olfactory ability, taste is virtually eliminated. 

Danilova V, Hellekant G (2003) Comparison of the responses of the chorda tympani and glossopharyngeal nerves to taste stimuli in C57BL/6J mice. BMC Neurosci 4 5 Dellisanti CD, Yao Y, Stroud JC, Wang ZZ, Chen L (2007) Crystal structure of the extracellular domain of nAChR alpha 1 bound to alpha-bungarotoxin at 1.94 A resolution. Nat Neurosci 10 953-962... 

Abbreviations CT, Chorda tympani CTX, Bilateral transection of the chorda tympani nerve DRK, Delayed-rectifying potassium FFA, Free fatty acid GL, Glossopharyngeal GLX, Bilateral transection of the glossopharyngeal nerve GPCR, G-protein-coupled receptor LCFA, Long-chain fatty acid PROP, 6-n-Propylthiouracil PTK, Protein tyrosine kinase PUFA, Polyunsaturated fatty acid NST, Nucleus of the solitary tract TG, Triglyceride TRC, Taste receptor cells TRPM5, Transient receptor potential protein 5... 

Guth L. 1957. The effects of glossopharyngeal nerve transection on the circumvallate papilla of the rat. Anat Rec 128 715-731. 

HanamoriT, Miller JJ Jr, Smith DV. 1988. Gustatory responsiveness of fibers in the hamster glossopharyngeal nerve. J Neurophysiol 60 478-498. 

The neuronal pathways that mediate hemodynamic regulation of vasopressin release are different from those involved in osmoregulation. Baroreceptors in the left atrium, left ventricle, and pulmonary veins sense blood volume (filling pressures), and baroreceptors in the carotid sinus and aorta monitor arterial blood pressure. Nerve impulses reach brainstem nuclei predominantly through the vagal trunk and glossopharyngeal nerve these signals ultimately are relayed to the SON and PVN. 

The carotid bodies have been known since 1743. They are small, pinkish neurovascular structures 1-2 mm in diameter they are located at the posterior aspect of the common carotid, where it divides into the internal and external carotids. Carotid bodies are vascularized by the occipital branch of the external carotid. The efferent nerve fibers of the carotid body converge into the carotid branch of the ninth cranial nerve, or glossopharyngeal nerve. 

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