Hydrogen peroxide via thromboxane A2 receptors mediates myogenic response of small skeletal muscle veins in rats.
Clin Hemorheol Microcirc
; 54(4): 393-407, 2013.
Article
em En
| MEDLINE
| ID: mdl-23478229
ABSTRACT
UNLABELLED We aimed to test two hypotheses (1) isolated small veins develop substantial myogenic tone in response to elevation of intraluminal pressure, (2) H2O2 contributes to the mediation of myogenic response via activation of arachidonic acid (AA) cascade and release constrictor prostaglandins. METHODS:
Small veins were isolated from gracilis muscle of male rats, then cannulated. Changes of diameter to increases in intraluminal pressure, H2O2 and arachidonic acid in the presence and absence of various inhibitors were measured by videomicroscope and microangiometer. At the end of experiments the passive diameter were obtained in Ca2+ -free PSS solution.RESULTS:
Isolated rat gracilis muscle small veins developed a substantial myogenic tone in response to increases in intraluminal pressure (1-12 mmHg). Calculated maximum myogenic tone was 70 ± 5% at 10 mmHg. Presence of catalase or indomethacin or SQ 29,548 reduced significantly the pressure-induced myogenic response. Also, H2O2 (10-9-10-5 M) and arachidonic acid (10-7-10-4 M) elicited concentration dependent constrictions, which were inhibited by the presence of indomethacin or SQ 29,548.CONCLUSION:
We propose that both myogenic response and pressure-induced release of H2O2 play important roles in regulating the vasomotor function of venules both in physiological and pathological conditions.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Músculo Esquelético
/
Receptores de Tromboxano A2 e Prostaglandina H2
/
Peróxido de Hidrogênio
Limite:
Animals
Idioma:
En
Revista:
Clin Hemorheol Microcirc
Assunto da revista:
ANGIOLOGIA
/
HEMATOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Hungria
País de publicação:
HOLANDA
/
HOLLAND
/
NETHERLANDS
/
NL
/
PAISES BAJOS
/
THE NETHERLANDS