Comparative acute effects of l-carnitine and dl-carnitine on hepatic catabolism of l-alanine and l-glutamine in rats

• 来源期刊: 中国药理学报（英文版）
• 关键词: carnitine liver metabolism gluconeogenesis ureagenesis l-glutamine
• 年，卷（期）: 2004,（10）
• 页码范围: 1257-1261
• 页数: 5页
• 语种: 英文

摘要

AIM: To compare the acute effects of l-carnitine (LCT) and dl-camitine (DLC) on hepatic catabolism of l-alanine andl-glutamine in rats. METHODS: Livers from 24 h fasted and fed rats were perfused in situ. The substrates l-alanine (5 mmol/L) and l-glutamine (5 mmol/L) were employed. The gluconeogenic and ureogenic activity was measured as the difference between the rates of glucose and urea released during and before the infusion of l-glutamine or l-alanine. RESULTS: LCT (60 μmol/L) but not DLC (60 μmol/L and 120 μmol/L) increased the production of glucose and urea froml-glutamine. However, neither LCT (60 μmol/L and 120 μmol/L) nor DLC (60 μmol/L and 240 μmol/L) showed any significant effect on hepatic glucose and urea production froml-alanine.CONCLUSION: The results showed a different acute effect of LCT and DLC on the activation of hepatic gluconeogenesis and ureagenesis promoted byl-glutamine, reinforcing the idea that DLC could not replace LCT.