Hsu J M
Prog Clin Biol Res. 1977;14:73-86.
The effects of zinc deficiency, in rats, on the levels of free amino acid in urine, plasma and skin extract were studied. In urine, significantly higher concentrations of taurine, urea, threonine, glutamic acid, valine, isoleucine, leucine and lysine were observed in zinc-deficient rats. In plasma, however, the levels of most individual amino acids in zinc-deficient rats were about the same as those in zinc-supplemented pair-fed controls with the exception of threonine, leucine and isoleucine. These three were significantly higher in rats receiving zinc-deficient diet. On the other hand, the zinc-supplemented ad libitum-fed rats had a significantly increased concentration of taurine, aspartic acid, threonine, serine, glutamic acid, alanine, lysine and arginine than either the pair-fed zinc-supplemented rats or zinc-deficient rats. In skin extracts, threonine, valine, leucine tyrosine, lysine, methionine, cystine, aspartic acid and alanine levels were significantly lower in zinc-deficient rats as compared to zinc-supplemented ad libitum-fed controls. However, the zinc-deficient rats had the same amount of methionine, cystine and glycine as the zinc-supplemented pair-fed rats. This observation suggests that the impairment of skin protein synthesis from injected labeled amino acids in zinc-deficient rats as opposed to zinc-supplemented pair-fed controls is not related to the availability or pool size of the precursors.
研究了大鼠缺锌对尿液、血浆和皮肤提取物中游离氨基酸水平的影响。在尿液中，缺锌大鼠的牛磺酸、尿素、苏氨酸、谷氨酸、缬氨酸、异亮氨酸、亮氨酸和赖氨酸浓度显著更高。然而，在血浆中，缺锌大鼠中大多数单个氨基酸的水平与补充锌的配对喂养对照组大致相同，但苏氨酸、亮氨酸和异亮氨酸除外。这三种氨基酸在接受缺锌饮食的大鼠中显著更高。另一方面，自由采食补充锌的大鼠中，牛磺酸、天冬氨酸、苏氨酸、丝氨酸、谷氨酸、丙氨酸、赖氨酸和精氨酸的浓度比配对喂养补充锌的大鼠或缺锌大鼠显著增加。在皮肤提取物中，与自由采食补充锌的对照组相比，缺锌大鼠的苏氨酸、缬氨酸、亮氨酸、酪氨酸、赖氨酸、蛋氨酸、胱氨酸、天冬氨酸和丙氨酸水平显著降低。然而，缺锌大鼠的蛋氨酸、胱氨酸和甘氨酸含量与配对喂养补充锌的大鼠相同。这一观察结果表明，与补充锌的配对喂养对照组相比，缺锌大鼠中注射标记氨基酸后皮肤蛋白质合成的受损与前体的可用性或储备量无关。
