Oxygen chemoreception by carotid body cells in culture.

Chemoreceptors for oxygen reside within the carotid body, but it is not known which cells actually sense hypoxia and by what mechanisms they transduce this information into afferent signals in the carotid sinus nerve. We have developed systems for the growth of glomus cells of the carotid body in dissociated cell culture. Here we demonstrate that, as in vivo, these cells contain the putative neurotransmitters dopamine, serotonin, and norepinephrine. Oxygen tension regulates the rate of dopamine secretion from the glomus cells. Similar to chemically stimulated catecholamine secretion from other adrenergic cells this hypoxia-stimulated release requires extracellular calcium. These results are compatible with the suggestion that the glomus cells of the carotid body are chemoreceptor cells and that they signal hypoxia by regulated secretion of dopamine.