The Central Nervous Organization of the Carotid Body Chemoreceptor Reflex
There is both anatomical and neurophysiological evidence to indicate that the primary synapses in the arterial chemoreceptor reflex are located within the nucleus tractus solitarius (NTS). Indeed, it appears that these afferents make connections with neurones in a relatively restricted portion of the NTS, particularly the commissural nucleus and the medial subnucleus in close proximity to the obex (for review see Donoghue et al., 1984; Housley et al., 1987; Jordan and Spyer, 1987). In contrast, there is little detailed evidence to support the notion that the respiratory neurones of the ventrolateral NTS are contacted directly by these afferents. The role of intrinsic circuits within the NTS in mediating the chemoreceptor control of respiratory activity, and the attended influence of this control on cardiovascular activity, have thus become a focus of interest in our laboratory. This report will summarize the results of neurophysiological, neuroanatomical, and immunocytochemical studies that have been designed to address these questions.
KeywordsCarotid Body Carotid Sinus Nucleus Tractus Solitarius Respiratory Neurone Carotid Baroreceptor
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