Biomaterial Database

Laryngeal-receptor responses to phasic CO2 in anesthetized cats. 1998

A Bradford, and D McKeogh, and R G O'Regan

Department of Physiology, Royal College of Surgeons in Ireland. abradfor@rcsi.ie

We compared the effects of CO2 applied continuously and during expiration on laryngeal-receptor activity in paralyzed, artificially ventilated and nonparalyzed, spontaneously breathing cats by using an isolated larynx, artificially ventilated to approximate a normal respiratory cycle. The majority of quiescent negative-pressure and all cold receptors were excited by 5 and 9% CO2 applied both continuously and during expiration. In general, quiescent positive-pressure, tonic negative-pressure, and tonic positive-pressure receptors were inhibited by 5 and 9% CO2 applied continuously and during expiration. There were no significant differences between responses to 5 and 9% CO2 or to continuous and expired CO2 or between paralyzed and nonparalyzed preparations. In conclusion, laryngeal receptors respond to changes in CO2 concentration occurring during a normal respiratory cycle. Because laryngeal-receptor stimulation exerts reflex effects on ventilation and upper airway muscle activity, these results suggest that airway CO2 plays a role in reflex regulation of breathing and upper airway patency.

UI	MeSH Term	Description	Entries
D007823	Laryngeal Nerves	Branches of the VAGUS NERVE. The superior laryngeal nerves originate near the nodose ganglion and separate into external branches, which supply motor fibers to the cricothyroid muscles, and internal branches, which carry sensory fibers. The RECURRENT LARYNGEAL NERVE originates more caudally and carries efferents to all muscles of the larynx except the cricothyroid. The laryngeal nerves and their various branches also carry sensory and autonomic fibers to the laryngeal, pharyngeal, tracheal, and cardiac regions.	Laryngeal Nerve, Superior,Laryngeal Nerve,Laryngeal Nerves, Superior,Nerve, Laryngeal,Nerve, Superior Laryngeal,Nerves, Laryngeal,Nerves, Superior Laryngeal,Superior Laryngeal Nerve,Superior Laryngeal Nerves
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
D008297	Male		Males
D009412	Nerve Fibers	Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.	Cerebellar Mossy Fibers,Mossy Fibers, Cerebellar,Cerebellar Mossy Fiber,Mossy Fiber, Cerebellar,Nerve Fiber
D002245	Carbon Dioxide	A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.	Carbonic Anhydride,Anhydride, Carbonic,Dioxide, Carbon
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D003080	Cold Temperature	An absence of warmth or heat or a temperature notably below an accustomed norm.	Cold,Cold Temperatures,Temperature, Cold,Temperatures, Cold
D005260	Female		Females
D000758	Anesthesia	A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
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