Carnitine import to isolated hepatocytes and synthesis are accelerated in pivalate-treated rats.
J Nutr
; 129(9): 1688-91, 1999 Sep.
Article
em En
| MEDLINE
| ID: mdl-10460205
ABSTRACT
To investigate the effect of pivalate on carnitine import and carnitine synthesis in the liver, we measured carnitine uptake in isolated rat hepatocytes with L-[(14)C] carnitine and concentrations of free carnitine, gamma-butyrobetaine and acylcarnitines using tandem mass spectrometry. Hepatocytes from rats treated with 20 mmol/L of pivalate for 4 wk had greater L-[(14)C] carnitine uptake than those of unsupplemented rats after 5, 10, 30 and 90 min. Addition of 1 mmol/L of pivalate or 1 mmol/L of pivaloylcarnitine to control cell suspensions did not affect L-[(14)C] carnitine uptake. The K(m) values for L-[(14)C] carnitine uptake for pivalate-treated rats were significantly lower than control (2.9 +/- 0.7 mmol/L for pivalate-treated rats, 6.2 +/- 1.1 mmol/L for controls). The concentration of free carnitine was not reduced in the liver of pivalate-treated rats, whereas the concentrations of acetylcarnitine and gamma-butyrobetaine were significantly lower than controls. In the heart and muscle the concentration of free carnitine was significantly lower and that of gamma-butyrobetaine was higher than controls. These results suggest that carnitine transport from plasma into the liver and synthesis in the liver are accelerated in rats with secondary carnitine deficiency induced by the administration of pivalate.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ácidos Pentanoicos
/
Carnitina
/
Fígado
Limite:
Animals
Idioma:
En
Revista:
J Nutr
Ano de publicação:
1999
Tipo de documento:
Article
País de afiliação:
Japão