title: Rostral ventral medullary surface activity during hypercapnic challenges in awake and anesthetized goats.
abstract: Regions within the rostral ventral medullary surface (RVMS) play an important role in cardiorespiratory responses to CO2 during anesthesia. Activity within a RVMS area, in which local cooling elicited marked ventilatory and blood pressure reductions, was measured as 660 nm scattered light changes in 5 goats following 5% CO2 challenges during waking and anesthetic states. During wakefulness, hypercapnia elicited a substantial, short latency transient (1-1.5 min) activity increase, followed by a sustained decrease. Stimulus cessation elicited a large and rapid off-transient activity increase which persisted for approximately 20 min. In contrast, during halothane anesthesia, the initial activation was absent, and the later activity decline and off-response were much reduced. We conclude that biphasic RVMS activity responses emerge to CO2 stimulation, and are state-dependent.
authors.affiliation: Department of Anatomy and Cell Biology, University of California at Los Angeles School of Medicine 90095-1763, USA.
authors.forename: D
authors.initials: D
authors.lastname: Gozal
authors.forename: P J
authors.initials: PJ
authors.lastname: Ohtake
authors.forename: D M
authors.initials: DM
authors.lastname: Rector
authors.forename: T F
authors.initials: TF
authors.lastname: Lowry
authors.forename: L G
authors.initials: LG
authors.lastname: Pan
authors.forename: H V
authors.initials: HV
authors.lastname: Forster
authors.forename: R M
authors.initials: RM
authors.lastname: Harper
mesh_terms: D000280:Administration, Inhalation; D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000494:pharmacology; D005260:Female; D006041:Goats; D006935:Hypercapnia / Q000503:physiopathology*; D008027:Light; D008526:Medulla Oblongata / Q000187:drug effects / Q000503:physiopathology*; D055095:Optics and Photonics; D011930:Reaction Time; D012119:Respiration / Q000187:drug effects; D012542:Scattering, Radiation; D014851:Wakefulness
chemical_list: D002245:Carbon Dioxide