Effects of protein content of diet and cortisol treatment on uptake of arginine by rat liver.
Experiments were conducted to determine whether the rate of entry of arginine into liver varies with changes in dietary protein or in the protein-catabolic state of the animal. It was first established by liver perfusion with [14C]ureidocitrulline that release of arginine by liver is sufficiently small that it can be ignored and that disappearance of arginine from a perfusion medium can be used to measure entry rate. Disappearance rates of arginine were then determined for rats that had been starved of fed either a stock control diet, a 15% casein diet, a 90% casein diet, or which had been injected with cortisol. There was no difference in arginine uptake between the control and 15% casein groups. The high protein group showed a threefold increase in rate of entry of arginine into liver as compared with the control group. Cortisol treatment and 48 hours of starvation also caused a threefold increase in arginine uptake. Cortisol treatment combined with high protein adaptation resulted in a sevenfold increase over controls. It was concluded that rate of entry of arginine into rat liver varies with nutritional and endocrine states.
D000818:Animals; D001120:Arginine / Q000378:metabolism*; D002364:Caseins / Q000008:administration & dosage; D002956:Citrulline / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage*; D006854:Hydrocortisone / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010477:Perfusion; D011506:Proteins / Q000378:metabolism; D051381:Rats
D002364:Caseins; D004044:Dietary Proteins; D011506:Proteins; D002956:Citrulline; D001120:Arginine; D006854:Hydrocortisone