Biomaterial Database

Laryngeal regulation of airway resistance. I. Chemoreceptor reflexes. 1980

T V McCaffrey, and E B Kern

The resistance of the larynx to airflow was measured during hypercapnia, hypoxemia, and stimulation of peripheral chemoreceptors by sodium cyanide and phenyl diguanide in 15 dogs anesthetized with alpha-chloralose (80 mg/kg). Laryngeal airway resistance (R1x) was obtained by measuring the pressure difference between the subglottic region and the mouth while a constant flow of humidified air was passed through the larynx. During spontaneous respiration, R1x varies with the phase of the respiratory cycle: R1x is high during expiration (mean +/- SEM = 0.79 +/- 0.19 cm H2O/L/sec) and falls just before inspiration (0.49 +/- 0.14 cm H2O/L/sec) and remains low until the end of inspiration. Hypercapnia, hypoxemia, and chemoreceptor stimulation each stimulated respiration and simultaneously decreased R1x during both inspiration and expiration. Chemoreceptor stimulation with phenyl diguanide (100 microgram/kg) and sodium cyanide (100 microgram/kg) produced similar decreases in R1x whether injected into the right atrium or left ventricle, indicating that these agents are not stimulating pulmonary receptors. The decrease in R1x during stimulation of chemoreceptors will decrease the work of ventilation. This study suggests that the control of ventilation involves the active regulation of the resistance of the laryngeal airway.

UI	MeSH Term	Description	Entries
D007830	Larynx	A tubular organ of VOICE production. It is located in the anterior neck, superior to the TRACHEA and inferior to the tongue and HYOID BONE.	Anterior Commissure, Laryngeal,Anterior Commissure, Larynx,Laryngeal Anterior Commissure,Laryngeal Posterior Commissure,Posterior Commissure, Laryngeal,Posterior Commissure, Larynx,Anterior Commissures, Laryngeal,Anterior Commissures, Larynx,Commissure, Laryngeal Anterior,Commissure, Laryngeal Posterior,Commissure, Larynx Anterior,Commissure, Larynx Posterior,Commissures, Laryngeal Anterior,Commissures, Laryngeal Posterior,Commissures, Larynx Anterior,Commissures, Larynx Posterior,Laryngeal Anterior Commissures,Laryngeal Posterior Commissures,Larynx Anterior Commissure,Larynx Anterior Commissures,Larynx Posterior Commissure,Larynx Posterior Commissures,Posterior Commissures, Laryngeal,Posterior Commissures, Larynx
D012018	Reflex	An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D002628	Chemoreceptor Cells	Cells specialized to detect chemical substances and relay that information centrally in the nervous system. Chemoreceptor cells may monitor external stimuli, as in TASTE and OLFACTION, or internal stimuli, such as the concentrations of OXYGEN and CARBON DIOXIDE in the blood.	Chemoreceptive Cells,Cell, Chemoreceptive,Cell, Chemoreceptor,Cells, Chemoreceptive,Cells, Chemoreceptor,Chemoreceptive Cell,Chemoreceptor Cell
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D006935	Hypercapnia	A clinical manifestation of abnormal increase in the amount of carbon dioxide in arterial blood.
D000403	Airway Resistance	Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.	Airway Resistances,Resistance, Airway,Resistances, Airway
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000860	Hypoxia	Sub-optimal OXYGEN levels in the ambient air of living organisms.	Anoxia,Oxygen Deficiency,Anoxemia,Deficiency, Oxygen,Hypoxemia,Deficiencies, Oxygen,Oxygen Deficiencies
D012966	Sodium Cyanide	A highly poisonous compound that is an inhibitor of many metabolic processes and is used as a test reagent for the function of chemoreceptors. It is also used in many industrial processes.	Cyanogran,Cyanide, Sodium