Ca2 + Dynamics in chemoreceptor cells: an overview

Abstract

The carotid body (CB) was defined as a sensory organ by De Castro in 1928. Two years later, Heymanns and coworkers demostrated that the organ was sensitive to alterations in blood gases and pH, in such a way that a decrease in blood P02 or pH or an increase in blood PC02 produced activation of the CB and, reflexely, hyperventilation. De Castro postulated that glomus cells were the sensor structures and that they should release sorn substance to transmit the stimulus to the sensory nerve endings (De Castro, 1928). De Castro's point of view, was widely accepted, and therefore the CB was considered a secondary sensory receptor. As a consequence, the principal aims of many workers in the chemoreception field have been to define the nature of the sensing mechanims ( sensory transduction process ) and to identify the substances released by chern cells.