Sympathetic activity during passive heat stress in healthy aged humans
Gagnon D, Schlader ZJ, Crandall CG
The Journal of physiology · 50 citas
Etiquetas de revisión
Solo mecanismosDatos neutrales que nuestra revisión registró sobre cómo se hizo este estudio. Describen el método, nunca si nos gusta el resultado.
Cómo se estudió
- Diseño
- Ensayo clínico controlado (clasificado por nuestro filtro de IA)
- Estudiado en
- Personas
- Resultado principal
- Solo mecanismos
Quién lo pagó
- Financiación
- Financiación independiente
- Gobierno
- National Heart, Lung, and Blood Institute
- Gobierno
- NHLBI NIH HHS
- Subvenciones
- National Heart, Lung, and Blood Institute (HL61388); National Heart, Lung, and Blood Institute (HL-84072)
Según 2 financiadores declarados.
Publicación
- Publicado
- 2015-03-05 · J Physiol · vol. 593 · número 9 · págs. 2225–2235
- Editorial
- Wiley
- Citado
- 58 citas · más que el 93% de estudios similares · 3.7× el promedio de su campo
- Impacto
- Entre el 10 % más citado de su campo
- Referencias
- 44 trabajos
- Acceso
- Acceso abierto (copia en repositorio)
- Áreas de investigación
- Thermoregulation and physiological responses · Climate Change and Health Impacts · Infrared Thermography in Medicine
- Palabras clave
- Cold pressor test, Blood pressure, Medicine, Heat stress, Internal medicine, Sympathetic activity, Sympathetic nervous system, Heart rate, Catecholamine, Endocrinology, Animal science
- MeSH
- muscle, skeletal, sympathetic nervous system, humans, catecholamines, reflex, aging, adult, aged, female, male, hemodynamics, hot temperature, stress, physiological
3 autores
- Daniel Gagnon🇺🇸Texas Health Dallas; Institute for Exercise and Environmental Medicine
- Zachary J. Schlader🇺🇸🇧🇪Texas Health Dallas; Nutrition Sciences (Belgium); Institute for Exercise and Environmental Medicine; University at Buffalo, State University of New York
- Craig G. Crandall🇺🇸 · autor de correspondenciaTexas Health Dallas; Institute for Exercise and Environmental Medicine
Resumen
El texto original del estudio, en el idioma en que se publicó.
Key points
Cardiovascular adjustments to heat stress are attenuated in healthy aged individuals, which could contribute to their greater prevalence of heat-related illnesses and deaths during heat waves. The attenuated cardiovascular adjustments in the aged could be due to lower increases in sympathetic nerve activity during heat stress. We examined muscle sympathetic nerve activity (MSNA) and plasma catecholamine concentrations in healthy young and aged individuals during whole-body passive heat stress. The main finding of this study is that increases in MSNA and plasma catecholamine concentrations did not differ between young and aged healthy individuals during passive heating. Furthermore, the increase in these variables did not differ when a cold pressor test and lower body negative pressure were superimposed upon heating. These findings suggest that attenuated cardiovascular adjustments to heat stress in healthy aged individuals are unlikely to be related to attenuated increases in sympathetic activity.
Abstract
Cardiovascular adjustments during heat stress are generally attenuated in healthy aged humans, which could be due to lower increases in sympathetic activity compared to the young. We compared muscle sympathetic nerve activity (MSNA) between 11 young (Y: 28 ± 4 years) and 10 aged (A: 70 ± 5 years) subjects prior to and during passive heating. Furthermore, MSNA responses were compared when a cold pressor test (CPT) and lower body negative pressure (LBNP) were superimposed upon heating. Baseline MSNA burst frequency (Y: 15 ± 4 vs. A: 31 ± 3 bursts min(-1) , P ≤ 0.01) and burst incidence (Y: 26 ± 8 vs. A: 50 ± 7 bursts (100 cardiac cycles (CC))(-1) , P ≤ 0.01) were greater in the aged. Heat stress increased core temperature to a similar extent in both groups (Y: +1.2 ± 0.1 vs. A: +1.2 ± 0.0°C, P = 0.99). Absolute levels of MSNA remained greater in the aged during heat stress (burst frequency: Y: 47 ± 6 vs. A: 63 ± 11 bursts min(-1) , P ≤ 0.01; burst incidence: Y: 48 ± 8 vs. A: 67 ± 9 bursts (100 CC)(-1) , P ≤ 0.01); however, the increase in both variables was similar between groups (both P ≥ 0.1). The CPT and LBNP further increased MSNA burst frequency and burst incidence, although the magnitude of increase was similar between groups (both P ≥ 0.07). These results suggest that increases in sympathetic activity during heat stress are not attenuated in healthy aged humans.
Resumen vía Europe PMC. Los derechos de autor siguen siendo de los autores o la editorial.
Confianza de la comunidad
Cargando…
¿Cuánto confías en los hallazgos de este estudio?
Comentarios
¿Algo está mal aquí?
Señala este estudio si su información, etiquetas o financiación parecen incorrectas. Un editor revisa cada señalamiento.
Información educativa sobre investigación publicada. No es consejo médico ni una recomendación para empezar o dejar nada.