Acute effects of sublingual nitroglycerin on cardiovagal and sympathetic baroreflex sensitivity.
Am J Physiol Regul Integr Comp Physiol
; 321(4): R525-R536, 2021 10 01.
Article
en En
| MEDLINE
| ID: mdl-34378422
The effects of nitroglycerin (glyceryl trinitrate, GTN) on baroreflex sensitivity (BRS) are incompletely understood. Moreover, there are no reports evaluating the acute responses in both the sympathetic BRS (SBRS) and the cardiovagal BRS (CBRS) to the administration of sublingual GTN. We hypothesized that sublingual GTN modulates both CBRS and SBRS. In 10 healthy subjects, beat-to-beat heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA) were recorded before and for 10 min after sublingual administration of GTN 0.4 mg. SBRS was evaluated from the relationship between spontaneous variations in diastolic BP and MSNA. CBRS was assessed with the sequence technique. These variables were assessed during baseline, during 3rd-6th min (post A), and 7th-10th min (post B) after GTN administration. Two min after GTN administration, MSNA increased significantly and remained significantly elevated during recording. Compared with baseline, CBRS decreased significantly (post A: 12.9 ± 1.6 to 7.1 ± 1.0 ms/mmHg, P < 0.05), whereas SBRS increased significantly (post A: 0.8 ± 0.2 to 1.5 ± 0.2 units·beat-1·mmHg-1, P < 0.05) with an upward shift of the operating point. There were no differences in these variables between posts A and B. A clinical dose of GTN increased MSNA rapidly through effects on both CBRS and SBRS. These effects should be kept in mind when nitrates are used to clinically treat chest pain and acute coronary syndromes and used as vasodilators in experimental settings.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sistema Nervioso Simpático
/
Nervio Vago
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Vasodilatadores
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Nitroglicerina
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Barorreflejo
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Músculo Esquelético
/
Corazón
Tipo de estudio:
Diagnostic_studies
Límite:
Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Am J Physiol Regul Integr Comp Physiol
Asunto de la revista:
FISIOLOGIA
Año:
2021
Tipo del documento:
Article
Pais de publicación:
Estados Unidos