Kidneys of adult animals serve as a major biosynthetic source of arginine. Recently, we
demonstrated that kidneys of rats infused with citrulline responded to the elevated plasma
citrulline concentrations by increasing citrulline uptake and producing greater quantities of
arginine. The objective of the present study was to determine the effects of feeding adult
male rats different levels of arginine or protein on renal arginine synthesis. Feeding arginine
(0, 0.5 and 2.0%) for 1 wk increased circulating plasma concentrations of arginine 2.5-fold …