Restoration of Chemoreflexes after Unilateral Carotid Deafferentation
The main arterial chemoreceptor organs in mammals are the carotid and aortic bodies. Each carotid body receives its sensory innervation from the carotid (sinus) branch of the ipsilateral glossopharyngeal nerve, with most of the somata of these chemosensory neurons located in the petrosal ganglion. The aortic bodies are innervated by the aortic (depressor) branches of the vagus nerves and the corresponding perikarya are located in the nodose ganglia. The central projections of these buffer nerves converge into the nucleus tractus solitarius (NTS). In fact, single NTS neurons may be excited by stimulation of both carotid and aortic afferents (Donoghue et al., 1985). Therefore, one is tempted to ask if these multiple inputs represent merely redundant afferent pathways for such vital responses as the ventilatory chemoreflexes initiated by hypoxia.
KeywordsCarotid Body Ventilatory Response Nucleus Tractus Solitarius Nodose Ganglion Hypoxic Ventilatory Response
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