Biomaterial Database

Pulmonary afferent and central influences on respiratory phase-switching in the cat. 1981

M I Cohen

A striking feature of the mammalian respiratory rhythm generator is the abruptness of the transitions between the inspiratory (I) and expiratory (E) phases ("phase-switching"). Although reciprocal inhibitory actions between I and E neurons are important for maintaining the alternation of respiratory phases, phase-switching actions are probably produced by recurrent inhibitory neuronal loops acting within each phase. The operation of such negative feedback circuits has been studied using two types of experimental input: (a) activation of pulmonary stretch receptors by lung inflation, which shortens the I phase and prolongs the E phase, and (b) electrical stimulation in the rostral pontine "pneumotaxic center" region, which can produce premature I leads to E or E leads to I switching, depending on stimulation site. These inputs produce diverse effects on discharges of various types of medullary respiratory neuron; analysis of such observations has led to hypotheses about the possible roles of different neuron populations in phase-switching.

UI	MeSH Term	Description	Entries
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D011149	Pons	The front part of the hindbrain (RHOMBENCEPHALON) that lies between the MEDULLA and the midbrain (MESENCEPHALON) ventral to the cerebellum. It is composed of two parts, the dorsal and the ventral. The pons serves as a relay station for neural pathways between the CEREBELLUM to the CEREBRUM.	Pons Varolii,Ponte,Pons Varolius,Pontes,Varolii, Pons,Varolius, Pons
D011661	Pulmonary Stretch Receptors	Stretch receptors found in the bronchi and bronchioles. Pulmonary stretch receptors are sensors for a reflex which stops inspiration. In humans, the reflex is protective and is probably not activated during normal respiration.	Receptors, Pulmonary Stretch,Receptors, Stretch, Pulmonary,Stretch Receptors, Pulmonary,Lung Stretch Receptors,Receptors, Stretch, Lung,Stretch Receptors, Lung,Lung Stretch Receptor,Pulmonary Stretch Receptor,Receptor, Lung Stretch,Receptor, Pulmonary Stretch,Receptors, Lung Stretch,Stretch Receptor, Lung,Stretch Receptor, Pulmonary
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
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
D000344	Afferent Pathways	Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.	Afferent Pathway,Pathway, Afferent,Pathways, Afferent
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