Ventral medullary surface activity during hypoxia in awake and anesthetized goats. Respir Physiol 1996 Jan;103(1):45-56
Date
01/01/1996Pubmed ID
8822222DOI
10.1016/0034-5687(95)00076-3Scopus ID
2-s2.0-0030070303 (requires institutional sign-in at Scopus site) 10 CitationsAbstract
The rostral ventrolateral medullary surface (VMS) plays a major state-dependent role in the control of breathing; its role during hypoxia remains speculative. We therefore assessed activity within the rostral VMS by measuring reflectance of scattered light in 5 goats during normoxia, hypoxia, and hyperoxia in awake and halothane anesthetic states. Within the first minute of hypoxia, light reflectance began to decrease in the awake state; reflectance reached a stable nadir within 30 min about 10 and 17% below control values (P < 0.01), at 12 and 10% inspired O2, respectively. In the anesthetized state, reflectance decreased (P < 0.01) by 6% at 10% inspired O2. After 30 min in the awake state, reflectance returned (P < 0.01) toward control values, reaching a stable level at 7 and 11% below control at 12 and 10% inspired O2, respectively (P < 0.05). Hyperoxia resulted in a 1% increase (P < 0.05) in reflectance. Changes in reflectance during hypoxia did not consistently parallel changes in breathing, heart rate, or arterial blood pressure. We conclude that, a) decreased reflectance during hypoxia results, in part, from increased neural activity, and b) state exerts a substantial effect on the response of VMS areas to hypoxia.
Author List
Forster HV, Gozal D, Harper RM, Lowry TF, Ohtake PJ, Pan LG, Rector DMAuthor
Hubert V. Forster PhD Professor in the Physiology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnesthesiaAnimals
Blood Pressure
Brain
Female
Fiber Optic Technology
Goats
Halothane
Heart Rate
Hypoxia
Light
Neurons
Oxygen
Partial Pressure
Respiration
Scattering, Radiation
Tidal Volume
