The effects of MEK1/2 inhibition on cigarette smoke exposure-induced ET receptor upregulation in rat cerebral arteries.
Toxicol Appl Pharmacol
; 304: 70-8, 2016 08 01.
Article
em En
| MEDLINE
| ID: mdl-27212444
ABSTRACT
Cigarette smoking, a major stroke risk factor, upregulates endothelin receptors in cerebral arteries. The present study examined the effects of MEK1/2 pathway inhibition on cigarette smoke exposure-induced ET receptor upregulation. Rats were exposed to the secondhand smoke (SHS) for 8weeks followed by intraperitoneal injection of MEK1/2 inhibitor, U0126 for another 4weeks. The urine cotinine levels were assessed with high-performance liquid chromatography. Contractile responses of isolated cerebral arteries were recorded by a sensitive wire myograph. The mRNA and protein expression levels of receptor and MEK/ERK1/2 pathway molecules were examined by real-time PCR and Western blotting, respectively. Cerebral artery receptor localization was determined with immunohistochemistry. The results showed the urine cotinine levels from SHS exposure group were significantly higher than those from the fresh group. In addition, the MEK1/2 inhibitor, U0126 significantly reduced SHS exposure-increased ETA receptor mRNA and protein levels as well as contractile responses mediated by ETA receptors. The immunoreactivity of increased ETA receptor expression was primarily cytoplasmic in smooth muscle cells. In contrast, ETB receptor was noted in endothelial cells. However, the SHS-induced decrease in endothelium-dependent relaxation was unchanged after U0126 treatment. Furthermore, SHS increased the phosphorylation of MEK1/2 and ERK1/2 protein in cerebral arteries. By using U0126 could inhibit the phosphorylated ERK1/2 protein but not MEK1/2. Taken together, our data show that treatment with MEK1/2 pathway inhibitor offsets SHS exposure-induced ETA receptor upregulation in rat cerebral arteries.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Poluição por Fumaça de Tabaco
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Butadienos
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Artérias Cerebrais
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Sistema de Sinalização das MAP Quinases
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Receptor de Endotelina A
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Receptor de Endotelina B
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Nitrilas
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Toxicol Appl Pharmacol
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
China