How the carotid body works: Different strategies and preparations to solve different problems

Abstract

This is a review of the different experimental approaches developed to solve the problems in our progress towards a comprehensive understanding of how arterial chemoreceptors operate. An analysis is performed of the bases, advantages and limits of the following preparations: studies of ventilatory reflexes originated from carotid bodies (CBs) in the entire animal; recordings of CB chemosensory discharges in situ; CB preparations perfused in situ; CB explants in oculo; CB explants in ovo; CB preparations incubated in vitro; CB preparations superfused in vitro; CB preparations perfused and superfused in vitro; CB tissue slices in vitro; cells acutely dissociated from CBs; CB cells in tissue culture; petrosal ganglia superfused in vitro; petrosal ganglion cells in tissue culture; and co-cultures of CB and sensory ganglion cells. A brief historical account is given of the passage from one preparation to the next one. Emphasis is placed on personal experience with the different preparations whenever possible. Examples are given of the importance of selecting the appropriate experimental preparation for solving each particular theoretical problem. In fact, brilliant ideas on how the CB works have been unproductive until finding the adequate experimental approach to explore the validity of such ideas.

Impaired chemoreflex sensitivity during septic shock induced by cecal ligation and perforation

“…Peripheral chemoreceptors that, in rats, are located mainly in the carotid body glomus cells (Sapru and Krieger 1977), have been identified as the primary oxygen sensors. These sensors respond to changes in blood pO 2 within milliseconds, contributing to ventilatory and cardiovascular regulation (Eyzaguirre and Zapata 1984;Iturriaga et al 1994;Zapata and Larraín 2005).…”

Prelimbic but not infralimbic cortex is involved in the pressor response to chemoreflex activation in awake rats

“…The chemoreflex is an important neural mechanism involved in cardiovascular and respiratory control. Peripheral chemoreceptors, which in rats are located mainly in the carotid body glomus cells (Sapru & Krieger, 1977), are identified as the primary oxygen sensors and respond to changes in blood within milliseconds, contributing to ventilatory and cardiovascular regulation (Eyzaguirre & Zapata, 1984; Iturriaga et al 1994; Lahiri et al 2001; Zapata & Larrain, 2005).…”

Sex Differences in Histomorphology of the Human Carotid Body

“…This is at variance with reports that there are no structural differences between male and female HCB [14]. The high vascularity of HCB is essential to its function for detecting changes in the composition of blood [18][19][20].…”