[Imbalance through lysine excess and correction by a threonine supplement, as a function of nutritional status].
Influence of lysine excess, with or without threonine supplementation, on body weight repletion after fasting, liver composition and liver, plasma and muscle free aminoacids, was studied on male adult rats (200g). Animals received either a mixed diet ad libitum (8 p. 100 protein) containing 1.05 p. 100 lysine, or a protein meal (1.1 g protein) supplying 145 mg of lysine per day given at 09.00 hour with free access to a protein-free diet for the rest of the day (separate feeding). The results show: --in animals fed a mixed diet, some effects of lysine excess are observed only on the free aminoacids, and muscular "RNA/DNA" ratio, but with a small amplitude; --in separate feeding, lysine excess has a negative effect upon body weight gain, hepatic and muscular "protein/DNA" and "RNA/DNA" ratios and the liver, plasma and muscle free aminoacids; --a supplement of threonine completely alleviates the effects of lysine excess, as well in mixed feeding as in separate feeding; --the best indicators of the aminoacid balance are the muscle "RNA/DNA" ratio and the liver, plasma and muscle free aminoacids; --separate feeding is a more sensitive method than mixed feeding for studying excess lysine unbalance, since such unbalance is obtained with a low level of lysine intake.
D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D001835:Body Weight; D004044:Dietary Proteins; D005215:Fasting; D008099:Liver / Q000378:metabolism; D008239:Lysine / Q000009:adverse effects*; D008297:Male; D009132:Muscles / Q000378:metabolism; D009748:Nutrition Disorders / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D051381:Rats; D013912:Threonine / Q000627:therapeutic use*
D000596:Amino Acids; D004044:Dietary Proteins; D013912:Threonine; D012313:RNA; D008239:Lysine
Désquilibre par excès de lysine et correction par un supplément de thréonine, en fonction des modalités alimentaires