title: Ornithine uptake by isolated hepatocytes and distribution within the cell.
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.
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D003600:Cytosol / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008239:Lysine / Q000494:pharmacology; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism; D009952:Ornithine / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D009952:Ornithine; D008239:Lysine