Publicação: Vagal afferent control of abdominal expiratory activity in response to hypoxia and hypercapnia in rats
Carregando...
Data
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Tipo
Artigo
Direito de acesso
Acesso restrito
Resumo
In the present study, we tested the hypothesis that vagal afferent information modulates the pattern of expiratory response to hypercapnia and hypoxia. Simultaneous recordings of airflow, diaphragmatic (DIA) and oblique abdominal muscle (ABD) activities were performed in anesthetized (urethane, 1.2 g/kg), tracheostomized, spontaneously breathing male Wistar rats (290-320 g, n=12). The animals were exposed to hypercapnia (7 and 10% CO2 for 5 min) and hypoxia (7% O-2 for 1 min) before and after bilateral vagotomy. We verified that the percentage increase in DIA burst amplitude elicited by hypercapnia and hypoxia episodes was similar between intact and vagotomized rats (P>0.05). In contrast, hypercapnia and hypoxia promoted a marked increase in ABD activity in vagotomized, but not in intact rats (P < 0.01). These amplified expiratory motor changes after vagotomy were associated with enhanced expiratory airflow (P < 0.01) and augmented tidal volume responses (P < 0.01). Our data indicates that, in anesthetized conditions, the removal of peripheral afferent inputs facilitates the processing of active expiration in response to hypercapnia and hypoxia in rats. (C) 2014 Elsevier B.V. All rights reserved.
Descrição
Palavras-chave
Active expiration, Electromyography, Hypercapnia, Hypoxia, Vagotomy, Pulmonary stretch receptors
Idioma
Inglês
Como citar
Respiratory Physiology & Neurobiology. Amsterdam: Elsevier Science Bv, v. 203, p. 90-97, 2014.
