Neural mechanism of the pressor response to obstructive and nonobstructive apnea.
J Appl Physiol (1985)
; 83(6): 2048-54, 1997 Dec.
Article
em En
| MEDLINE
| ID: mdl-9390980
ABSTRACT
Obstructive and nonobstructive apneas elicit substantial increases in muscle sympathetic nerve activity and arterial pressure. The time course of change in these variables suggests a causal relationship; however, mechanical influences, such as release of negative intrathoracic pressure and reinflation of the lungs, are potential contributors to the arterial pressure rise. To test the hypothesis that apnea-induced pressor responses are neurally mediated, we measured arterial pressure (photoelectric plethysmography), muscle sympathetic nerve activity (peroneal microneurography), arterial O2 saturation (pulse oximeter), and end-tidal CO2 tension (gas analyzer) during sustained Mueller maneuvers, intermittent Mueller maneuvers, and simple breath holds in six healthy humans before, during, and after ganglionic blockade with trimethaphan (3-4 mg/min, titrated to produce complete disappearance of sympathetic bursts from the neurogram). Ganglionic blockade abolished the pressor responses to sustained and intermittent Mueller maneuvers (-4 +/- 1 vs. +15 +/- 3 and 0 +/- 2 vs. +15 +/- 5 mmHg) and breath holds (0 +/- 3 vs. +11 +/- 3, all P < 0.05). We conclude that the acute pressor response to obstructive and nonobstructive voluntary apnea is sympathetically mediated.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Apneia
/
Síndromes da Apneia do Sono
/
Sistema Nervoso Autônomo
/
Pressão Sanguínea
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
J Appl Physiol (1985)
Assunto da revista:
FISIOLOGIA
Ano de publicação:
1997
Tipo de documento:
Article
País de afiliação:
Estados Unidos