分离的肝细胞对鸟氨酸的摄取及其在细胞内的分布。

Ornithine uptake by isolated hepatocytes and distribution within the cell.

作者信息

Zollner H

出版信息

Int J Biochem. 1984;16(6):681-5. doi: 10.1016/0020-711x(84)90038-7.

Abstract

Uptake of ornithine by isolated hepatocytes and its distribution within the cell was investigated. Ornithine uptake was energy independent and exhibited a saturable and a nonsaturable component. The Km value of the saturable component was 1.3 mM. At an external ornithine concentration of 0.5 mM the rate of ornithine uptake was 127 +/- 19 nmol/g. Lysine inhibited ornithine uptake, indicating the existence of an ornithine transport system. It was concluded that ornithine transport can limit urea synthesis in the state of transition from a low ammonia to a high ammonia supply.

摘要

研究了分离的肝细胞对鸟氨酸的摄取及其在细胞内的分布。鸟氨酸摄取不依赖能量，并表现出一个可饱和成分和一个非可饱和成分。可饱和成分的Km值为1.3 mM。在外部鸟氨酸浓度为0.5 mM时，鸟氨酸摄取速率为127±19 nmol/g。赖氨酸抑制鸟氨酸摄取，表明存在鸟氨酸转运系统。得出的结论是，在从低氨供应状态转变为高氨供应状态时，鸟氨酸转运可能会限制尿素合成。