Alterations of epinephrine-induced gluconeogenesis in aging
Experimental & Molecular Medicine
; : 334-340, 2009.
Article
em En
| WPRIM
| ID: wpr-136587
Biblioteca responsável:
WPRO
ABSTRACT
The effects of glucagon and epinephrine on gluconeogenesis in young (4 month) and old (24 month) Fisher 344 rat hepatocytes were compared. In contrast to glucagon, which had a similar effect on gluconeogenesis in both young and old cells, epinephrine caused a smaller increase in gluconeogenesis in old rat hepatocytes than in young hepatocytes. beta2 adrenergic receptor (beta2-AR) expression slightly decreased in aged rat liver, and there were differences between young and old hepatocytes in their patterns of G protein coupled receptor kinases, which are involved in the activation of beta2-AR receptor signal desensitization. The major isoform of the kinase changed from GRK2 to GRK3 and the expression of beta-arrestin, which is recruited by the phosphorylated beta2-AR for internalization and degradation, increased in aged rat liver. GRK3 overexpression also decreased the glucose output from young rat hepatocytes. We conclude that an age-associated reduction in epinephrine-induced gluconeogenesis occurs through the epinephrine receptor desensitizing system.
Palavras-chave
Texto completo:
1
Índice:
WPRIM
Assunto principal:
Fosforilação
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Ratos Endogâmicos F344
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Envelhecimento
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Glucagon
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Epinefrina
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Receptores Adrenérgicos beta 2
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Agonistas Adrenérgicos beta
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Quinase 2 de Receptor Acoplado a Proteína G
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Quinase 3 de Receptor Acoplado a Proteína G
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Gluconeogênese
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Experimental & Molecular Medicine
Ano de publicação:
2009
Tipo de documento:
Article