Comparative aspects of central CO2 chemoreception
Related Experiment Video
Updated: Oct 23, 2026

Identification of Olfactory Volatiles using Gas Chromatography-Multi-unit Recordings (GCMR) in the Insect Antennal Lobe
Published on: February 24, 2013
1Department of Physiology, Dartmouth Medical School, Lebanon, NH 03756, USA.
Abstract:
We compare and contrast the putative mechanisms underlying CO2 chemoreceptor function in air breathing vertebrates and terrestrial pulmonate snails. We discuss the role of intracellular pH (pHi) in central respiratory responses to CO2 and describe a variety of patterns of pHi regulation in chemosensory areas. One pattern, in which pHi retains a fixed relationship to the CO2 stimulus over time, seems well suited to chemoreceptor cells. Alphastat regulation of ventilation is apparent in both air breathing vertebrates and terrestrial pulmonate snails. Diethyl pyrocarbonate inhibits respiratory responses to hypercapnia in both groups of animals. The neuronal basis of chemosensitivity is similar, in that putative chemoreceptor cells depolarize during hypercapnic stimulation, but the ionic basis of excitability appears to be a potassium conductance in the vertebrates studied to date and a calcium conductance in the snails. Despite divergent evolutionary histories, chemosensory responses and mechanisms are remarkably similar in air breathing vertebrates and terrestrial pulmonate snails.
More Related Videos
Related Concept Videos
Olfaction
The olfactory receptors are embedded in the cilia of the...
Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this principle...
G-Protein Gated Ion Channels
Sensory organs,...
Olfactory Receptors: Location and Structure
Chemical Factors Affecting Respiration Centers
CO2 has a potent influence on respiration and is strictly regulated. Under...
Physiology of Respiration II: Neurogenic Control of Respiration
Central Control
The brainstem is the primary site of central control, hosting respiratory centers:

