Selective Effect of Reduced Extracellular pH on Potassium Channels in Type-I Cells from the Neonatal Rat Carotid Body
A decrease in pH of arterial blood excites the carotid body even when the partial pressures of O2 and CO2 (the other natural stimuli of the carotid body) are maintained at a constant level1. The precise location within the carotid body where acidity, or any other chemoexcitatory agent acts remains unclear, although much evidence supports the view that the type-I glomus cells are the chemosensory elements of the carotid body2. These cells contain catecholamine-filled dense core vesicles and recent studies have shown them to possess various ion channels in their plasma membranes3,4,4,6. As ion channels have been shown to play key roles in other sensory cell types, an understanding of those present in type-I cells and their possible modulation by chemoexcitatory agents may prove to be essential to our understanding of the chemotransductive process.
KeywordsPatch Clamp Carotid Body Test Potential Bath Application Carotid Sinus Nerve
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