Respiration in Chronic Hypoxia and Hyperoxia: Role of Peripheral Chemoreceptors
The peripheral chemoreceptors (carotid and aortic bodies) are environmental monitors - they monitor internal milieu, and external as well, to the extent that it influences the internal milieu. These are the only oxygen sensing organs which generate protective reflex respiratory and autonomic responses against the ambient hypoxia. In the absence of their neural linkage with the central nervous system or during their malfunction in disease, the organism cannot detect oxygen deprivation in the milieu and hence cannot respond appropriately. This “gateway” function of the peripheral chemoreceptors makes it indispensable for protection, particularly for the altitude sojourners and for the patients with hypoxemic disease. These organs work harder at higher altitudes. This paper will focus on the adaptive responses of the carotid body to hypoxia of high altitudes. For contrast, the observations on carotid body of animals which were exposed to high oxygen pressure will also be included. The theme, relating structure to function of the carotid body, will be the running thread in the paper.
KeywordsCarotid Body Ventilatory Response Chronic Hypoxia Glomus Cell Peripheral Chemoreceptor
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