Alpha-bungarotoxin binding in cat carotid body

Abstract

The carotid body is an arterial chemosensory organ which detects changes in blood gas tensions and pH, and reflexly contributes to the cardiorespiratory adjustments which occur during hypoxia, hypercapnia and acidosis. However, the sensory mechanisms involved in carotid chemoreception remain to be elucidated. Morphologically, the carotid body consists of an association of elemental units, or glomeruli, within a connective tissue stroma penetrated by a dense capillary net 5. The glomeruli are comprised of catecholamine-rich type I, or chief cells, which are enveloped by glial-like processes of type II, or sustentacular, cellsa,4,19. Sensory fibers from the carotid sinus nerve penetrate the glomeruli to terminate in synaptic-like apposition on type I cellst,18, 21.