Can carotid body perfusion act as a respiratory controller?
The carotid bodies contain chemoreceptor cells that respond to hypoxia and hypercapnia/acidosis of the arterial blood. Since the carotid bodies receive exceptionally high blood perfusion through branches of the external carotid artery, their impulse activity to the respiratory center is thought to be determined mainly by the arterial partial pressures of oxygen (O(2)) and carbon dioxide (CO(2)). However, this paradigm explains the observed increase in ventilation neither during mentally agitated states nor physical exercise. The objective of the work was to test whether physiologically feasible reductions in carotid body perfusion could explain such respiratory overdrive using a flow-sensitive mathematical model of the carotid body chemoreception. The model is based on the law of mass balance and on the description of the chemical reactions in the arterial blood and inside the receptor cells. The neural response to the arterial O(2) and CO(2) levels is assumed to be mediated via the co
