High CO2/H+ dialysis in the caudal ventrolateral medulla (Loeschcke's area) increases ventilation in wakefulness

Autor(es)

da Silva, Glauber S. F. ^[1] ; Li, Aihua ^[2] ; Nattie, Eugene ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Physiol, FMRP, BR-05508 Sao Paulo - Brazil

^[2] Dartmouth Med Sch, Dept Physiol, Lebanon, NH 03756 - USA

• Tipo de documento: Artigo Científico
• Fonte: Respiratory Physiology & Neurobiology; v. 171, n. 1, p. 46-53, APR 15 2010.
• Citações Web of Science: 18

Resumo

Central chemoreception, the detection of CO(2)/H(+) within the brain and the resultant effect on ventilation, was initially localized at two areas on the ventrolateral medulla, one rostral (rVLM-Mitchell's) the other caudal (cVLM-Loeschcke's), by surface application of acidic solutions in anesthetized animals. Focal dialysis of a high CO(2)/H(+) artificial cerebrospinal fluid (aCSF) that produced a milder local pH change in unanesthetized rats (like that with a similar to 6.6 mm Hg increase in arterial P(CO2)) delineated putative chemoreceptor regions for the rVLM at the retrotrapezoid nucleus and the rostral medullary raphe that function predominantly in wakefulness and sleep, respectively. Here we ask if chemoreception in the cVLM can be detected by mild focal stimulation and if it functions in a state dependent manner. At responsive sites just beneath Loeschcke's area, ventilation was increased by, on average, 17% (P < 0.01) only in wakefulness. These data support our hypothesis that central chemoreception is a distributed property with some sites functioning in a state dependent manner. (C) 2010 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 06/60696-5 - Papel do núcleo obscuro da rafe na quimiossensibilidade ao CO2/pH
• Beneficiário: Glauber dos Santos Ferreira da Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado