Peripheral Chemoreceptor Contributions to Cardiovascular Regulation

Oxygen homeostasis at the cellular level depends on acute and appropriate cardiovascular adjustments elicited by neural chemosensitive reflexes. This review addresses the integrated physiology of peripheral chemoreflex control of cardiovascular function with emphasis on the relevance for the intact and conscious human. Peripheral chemoreceptor activation affects sympathoexcitatory and cardiovascular responses that can be modified by the concurrent effects of enhanced ventilation. Additional changes in baroreflex control during chemoreceptor activation must be considered in determining chemoreflex-mediated cardiovascular regulation. Moreover, the autonomic response elicited by the peripheral chemoreflex may enhance the sensitivity of these chemoreceptors, further enhancing or prolonging the neural and cardiovascular consequences of hypoxia. Finally, the recent interest in the role of altered chemoreflex sensitivity and function in cardiovascular pathology is highlighted. The collective information suggests that these interactions may contribute importantly to cardiovascular pathology requiring considerable research into the linkage between cellular and genomic mechanisms that affect the integrated systems response in health and disease.