Effect of mild carboxy-hemoglobin on exercising skeletal muscle: intravascular and intracellular evidence.
Am J Physiol Regul Integr Comp Physiol
; 283(5): R1131-9, 2002 Nov.
Article
en En
| MEDLINE
| ID: mdl-12376406
We studied muscle blood flow, muscle oxygen uptake (VO(2)), net muscle CO uptake, Mb saturation, and intracellular bioenergetics during incremental single leg knee-extensor exercise in five healthy young subjects in conditions of normoxia, hypoxia (H; 11% O(2)), normoxia + CO (CO(norm)), and 100% O(2) + CO (CO(hyper)). Maximum work rates and maximal oxygen uptake (VO(2 max)) were equally reduced by approximately 14% in H, CO(norm), and CO(hyper). The reduction in arterial oxygen content (Ca(O(2))) (approximately 20%) resulted in an elevated blood flow (Q) in the CO and H trials. Net muscle CO uptake was attenuated in the CO trials. Suprasystolic cuff measurements of the deoxy-Mb signal were not different in terms of the rate of signal rise or maximum signal attained with and without CO. At maximal exercise, calculated mean capillary PO(2) was most reduced in H and resulted in the lowest Mb-associated PO(2). Reductions in ATP, PCr, and pH during H, CO(norm), and CO(hyper) occurred earlier during progressive exercise than in normoxia. Thus the effects of reduced Ca(O(2)) due to mild CO poisoning are similar to H.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Carboxihemoglobina
/
Ejercicio Físico
/
Músculo Esquelético
/
Mioglobina
Límite:
Adult
/
Humans
/
Male
Idioma:
En
Revista:
Am J Physiol Regul Integr Comp Physiol
Asunto de la revista:
FISIOLOGIA
Año:
2002
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos