L-NAME iontophoresis: a tool to assess NO-mediated vasoreactivity during thermal hyperemic vasodilation in humans.
J Cardiovasc Pharmacol
; 61(5): 361-8, 2013 May.
Article
em En
| MEDLINE
| ID: mdl-23318989
ABSTRACT
BACKGROUND:
Decreased endothelial Nitric oxide (NO) bioavailability is one of the earliest events of endothelial dysfunction. Assessment of microvascular blood flow using a Laser Doppler Imager during local noninvasive administration of L-N-Arginine-Methyl-Ester (L-NAME) by skin iontophoresis may help discriminate the relative contributions of NO and non-NO pathways during a skin thermal hyperemic test.METHODS:
In healthy nonsmokers, the effects of thermal vasodilation and sodium nitroprusside-mediated vasodilation were tested on skin pretreated with 0.9% saline solution, 2% L-NAME iontophoresis (n = 12), or intradermal injection of 25 nmol L-NAME (n = 10). The effects of L-NAME iontophoresis were also measured in a group of smokers (n = 10).RESULTS:
L-NAME iontophoresis and intradermal injection of L-NAME decreased the skin response to local heating to a similar degree (-41% ± 4% vs. -44% ± 6%). L-NAME iontophoresis site-to-site and day-to-day coefficients of correlation were 0.83 and 0.76, respectively (P < 0.01). The site-to-site and day-to-day coefficients of correlation of L-NAME injection were lower than those of iontophoresis at 0.66 (P < 0.05) and 0.12, respectively (P = not significant). Sodium nitroprusside-induced skin hyperemia was not affected by L-NAME administration. L-NAME iontophoresis-mediated inhibition of skin thermal hyperemia was greater in smokers than in nonsmokers (P < 0.05).CONCLUSIONS:
Laser Doppler Imager assessment of skin thermal hyperemia after L-NAME iontophoresis provides a reproducible and selective bedside method of qualitatively analyzing the contribution of the NO pathway to microvascular vasomotor function.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Pele
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Vasodilatação
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Iontoforese
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NG-Nitroarginina Metil Éster
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Inibidores Enzimáticos
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Hiperemia
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Hipertermia Induzida
Limite:
Adult
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Humans
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Male
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article