Laouari D, Jean G, Kleinknecht C, Broyer M
INSERM U.192, Hôpital Necker - Enfants Malades, Paris, France.
Pediatr Nephrol. 1991 May;5(3):318-22. doi: 10.1007/BF00867491.
The nutritional effects of low-protein diets are difficult to assess in humans. Normal and uraemic growing rats were therefore fed: a moderately low-protein (12%) reference diet (diet R), two 5% casein diets, one supplemented with essential amino acids (AA) (diet A) and the other with their keto acids (diet K), and a 7% casein diet isonitrogenous with diet K (diet L). Appetite and growth of both uraemic and control rats were identical on diets R and A and were reduced on diets K and L. Stunting was prominent in rats fed diet L and more severe than in those on diet K. Diet K induced marked anorexia in controls. This effect was smaller in uraemic rats, which were all anorectic, regardless of the diet. Plasma essential AA were similar in rats on diets R and A but low in control rats fed diets L and K. In particular, diet K did not improve the branched-chain AA levels although it produced better growth than diet L. Plasma and muscle threonine were surprisingly elevated in rats on the semi-synthetic diets A and K, despite identical or lower consumptions. Regardless of the diet, uraemia resulted in unchanged or increased plasma essential AA, despite reduced appetite and stunting. Uraemia caused a marked rise in some non-essential AA. Muscle essential AA, except for threonine, were essentially unaltered and did not correlate with growth or uraemia.
低蛋白饮食的营养作用在人类中很难评估。因此，给正常生长的大鼠和患尿毒症的生长大鼠喂食：一种适度低蛋白（12%）的对照饮食（饮食R）、两种5%酪蛋白饮食，一种添加必需氨基酸（饮食A），另一种添加其酮酸（饮食K），以及一种与饮食K等氮的7%酪蛋白饮食（饮食L）。饮食R和A喂养的尿毒症大鼠和对照大鼠的食欲和生长情况相同，而饮食K和L喂养的大鼠食欲和生长受到抑制。饮食L喂养的大鼠发育迟缓明显，且比饮食K喂养的大鼠更严重。饮食K导致对照大鼠出现明显的厌食。这种作用在尿毒症大鼠中较小，无论喂食何种饮食，尿毒症大鼠均有厌食情况。饮食R和A喂养的大鼠血浆必需氨基酸水平相似，但饮食L和K喂养的对照大鼠血浆必需氨基酸水平较低。特别是，饮食K虽然比饮食L使大鼠生长得更好，但并未提高支链氨基酸水平。尽管半合成饮食A和K的摄入量相同或更低，但喂食这两种饮食的大鼠血浆和肌肉中的苏氨酸含量却意外升高。无论喂食何种饮食，尽管尿毒症大鼠食欲下降且发育迟缓，但其血浆必需氨基酸水平却未改变或升高。尿毒症导致一些非必需氨基酸显著升高。除苏氨酸外，肌肉中的必需氨基酸基本未改变，且与生长或尿毒症无关。
