Biomaterial Database

Effect of graded cooling of intermediate areas on respiratory response to vagal input. 1984

D E Millhorn, and J P Kiley

The present study was undertaken to determine if the phrenic responses to vagally mediated inputs are also affected by focal cooling of the intermediate areas (IA) of the ventral medulla. Anesthetized, paralyzed cats whose vagi and carotid sinus nerves had been cut were studied. The IA were cooled focally with a thermostatically controlled thermode. When the IA were 40 degrees C, low intensity vagal stimulation caused inhibition of phrenic activity. The stimulus was also applied when IA were cooled to 30 and 20 degrees C. The magnitude of the inhibition was unaffected by the cooling. In another series of experiments, high intensity vagal stimulation was used. This led to an hyperpnea when IA were 40 degrees C. The magnitude of the response was much smaller when the test stimulus was given at lower IA temperatures. The effect of cooling IA on the phrenic response to mechanical stimulation of pulmonary stretch receptors and airway irritant receptors were also studied in cats with intact vagi. We found that the response to irritant receptor, but not to stretch receptor, stimulation was abolished by the cooling. We conclude that the intermediate areas are involved in the integration of afferent input from airway irritant receptors that reaches the respiratory controller via high threshold vagal afferents, but not involved in processing signals from pulmonary stretch receptors.

UI	MeSH Term	Description	Entries
D008526	Medulla Oblongata	The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.	Accessory Cuneate Nucleus,Ambiguous Nucleus,Arcuate Nucleus of the Medulla,Arcuate Nucleus-1,External Cuneate Nucleus,Lateral Cuneate Nucleus,Nucleus Ambiguus,Ambiguus, Nucleus,Arcuate Nucleus 1,Arcuate Nucleus-1s,Cuneate Nucleus, Accessory,Cuneate Nucleus, External,Cuneate Nucleus, Lateral,Medulla Oblongatas,Nucleus, Accessory Cuneate,Nucleus, Ambiguous,Nucleus, External Cuneate,Nucleus, Lateral Cuneate
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D010812	Physical Stimulation	Act of eliciting a response from a person or organism through physical contact.	Stimulation, Physical,Physical Stimulations,Stimulations, Physical
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
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
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
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
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures