Effects of cooling the ventrolateral medulla on diaphragm activity during NREM sleep. Respir Physiol 1996 Jul;104(2-3):127-35
Date
07/01/1996Pubmed ID
8893358DOI
10.1016/0034-5687(96)00025-4Scopus ID
2-s2.0-0030198452 (requires institutional sign-in at Scopus site) 10 CitationsAbstract
Dysfunction through cooling of neurons near the ventrolateral medullary (VLM) surface results in apnea in the anesthetized state, whereas similar neuronal dysfunction in the awake state only modestly decreases breathing. The purpose of this study was to investigate effects on breathing, as measured by diaphragm electromyogram (EMGdi), of VLM neuronal dysfunction during NREM sleep, a naturally occurring change in state. In six goats, thermodes for cooling were chronically implanted between the first hypoglossal rootlet and the pontomedullary junction (area M and area S). During wakefulness and NREM sleep, bilateral VLM cooling (thermode temp = 20 degrees C) for 30 sec decreased EMGdi mean activity and minute EMGdi (p < 0.05) and lengthened the time between diaphragm contractions. During NREM sleep, reductions in mean and minute EMGdi during cooling tended to be greater than during waking, but not significantly. However, following carotid body denervation. VLM cooling caused prolonged apnea during NREM sleep but only a brief apnea in the awake state. The data suggest that either intact VLM neuronal mechanisms or intact carotid afferents are necessary for sustained EMGdi activity during NREM sleep.
Author List
Ohtake PJ, Forster HV, Pan LG, Lowry TF, Korducki MJ, Whaley AAAuthor
Hubert V. Forster PhD Professor in the Physiology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBlood Pressure
Chemoreceptor Cells
Cold Temperature
Denervation
Diaphragm
Electrodes, Implanted
Electroencephalography
Electromyography
Female
Goats
Medulla Oblongata
Neurons
Respiratory Mechanics
Sleep
Wakefulness
