Hargrove D M, Rogers Q R, Calvert C C, Morris J G
Department of Physiological Science, School of Veterinary Medicine, University of California, Davis 95616.
J Nutr. 1988 Mar;118(3):311-20. doi: 10.1093/jn/118.3.311.
The effect of excesses of the branched-chain amino acids (BCAA), particularly leucine, on growth, food intake and plasma amino acid concentrations were investigated in kittens. Effects of excess leucine were tested in kittens fed five basal diets that varied in their nitrogen and amino acid contents. Compared to rats, kittens were much less sensitive to excesses of the BCAA. Addition of 10% leucine to basal diets that provided nitrogen just at or below the minimal requirement of kittens resulted in no change or increased growth and food intake of kittens when the isoleucine and valine concentrations in the basal diet were just at or slightly in excess of the kitten's minimal requirements for those amino acids. An adverse effect of leucine added to low nitrogen basal diets was observed only when isoleucine and valine were provided below the kitten's requirement (80% of requirement). When basal diets containing adequate nitrogen (24% amino acids) were tested, the addition of leucine (10%) resulted in an adverse effect when isoleucine and valine were provided at 80% of the kitten's requirement and in mild growth depressions when isoleucine and valine were provided at 1.1 times the requirement. Leucine-induced growth depression was alleviated by the addition of isoleucine and valine at 0.5%, indicating that excess leucine caused a BCAA antagonism or an amino acid imbalance. With the addition of leucine to the basal diets, there were consistent decreases in concentrations of alanine and tyrosine in plasma but no consistent depressions in the concentrations of isoleucine and valine.
研究了支链氨基酸（BCAA）过量，尤其是亮氨酸过量，对小猫生长、食物摄入量和血浆氨基酸浓度的影响。在喂食五种氮和氨基酸含量不同的基础日粮的小猫中测试了过量亮氨酸的影响。与大鼠相比，小猫对BCAA过量的敏感性要低得多。当基础日粮中异亮氨酸和缬氨酸的浓度刚好达到或略高于小猫对这些氨基酸的最低需求量时，在仅提供刚好达到或低于小猫最低需求量的氮的基础日粮中添加10%的亮氨酸，小猫的生长和食物摄入量没有变化或增加。仅当提供的异亮氨酸和缬氨酸低于小猫的需求量（需求量的80%）时，才观察到添加到低氮基础日粮中的亮氨酸有不良影响。当测试含充足氮（24%氨基酸）的基础日粮时，当提供的异亮氨酸和缬氨酸为小猫需求量的80%时，添加亮氨酸（10%）会产生不良影响，当提供的异亮氨酸和缬氨酸为需求量的1.1倍时，会出现轻度生长抑制。添加0.5%的异亮氨酸和缬氨酸可缓解亮氨酸诱导的生长抑制，这表明过量亮氨酸会导致BCAA拮抗或氨基酸失衡。在基础日粮中添加亮氨酸后，血浆中丙氨酸和酪氨酸的浓度持续下降，但异亮氨酸和缬氨酸的浓度没有持续降低。
