The relationship between anaerobic lactate threshold and plasma catecholamines during incremental exercise in hereditary spastic paraplegia.
Funct Neurol
; 18(2): 83-7, 2003.
Article
en En
| MEDLINE
| ID: mdl-12911138
ABSTRACT
Lower limb muscle chronic hyperactivity in hereditary spastic paraplegia (HSP) is the consequence of motor corticospinal tract involvement, which in turn has been hypothesized to be of mitochondrial origin. In order to assess skeletal muscle aerobic metabolism and sympathetic response during exercise in 10 HSP patients, we evaluated their blood lactate and catecholamine levels during an incremental workload bicycle exercise. Lactate, but not epinephrine or norepinephrine, levels were significantly higher in the HSP patients than in control subjects, in both resting conditions and during exercise. In the patients, the anaerobic lactate threshold was reached prematurely (at 50% of the predicted normal maximal power output) when compared to normal controls. This finding was not related to any specific muscle morphology or histochemical activity. Although other factors, including chronic spasticity and muscle deconditioning, have to be considered in the interpretation of our data, our results suggest the possible involvement of a mitochondrial mechanism, independently of sympathetic system overactivation, in exercising skeletal muscle of HSP patients.
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Banco de datos:
MEDLINE
Asunto principal:
Paraplejía Espástica Hereditaria
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Epinefrina
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Norepinefrina
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Esfuerzo Físico
/
Lactatos
Tipo de estudio:
Clinical_trials
/
Prognostic_studies
Límite:
Adult
/
Aged
/
Female
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
Funct Neurol
Asunto de la revista:
NEUROLOGIA
Año:
2003
Tipo del documento:
Article
País de afiliación:
Italia