色氨酸及其代谢产物对兔晶状体电解质平衡的影响。

The influence of tryptophan and its metabolites upon rabbit lens electrolyte balance.

作者信息

Kishida K, Paterson C A, Delamere N A

出版信息

Curr Eye Res. 1982;2(5):309-15. doi: 10.3109/02713688209000775.

DOI:10.3109/02713688209000775

PMID:6219861

Abstract

The effect of tryptophan and three major metabolites of tryptophan on the rabbit lens electrolyte balance was examined. Even at 3 x 10(-3) M tryptophan, tryptamine and xanthurenic acid had no effect on lens sodium, potassium and calcium content after a 20 hr incubation. Small but significant changes in lens sodium and potassium content were induced by 20 hr incubation in 2 x 10(-3) M 3-hydroxy-DL-kynurenine and 10(-3) M hydroxyanthranilic acid. Lens Na, K-ATPase activity was unaffected by 3 x 10(-3) M tryptophan. Tryptamine reduced, to a small extent, Na,K-ATPase activity at 3 x 10(-3) M, but was without effect at 10(-3) M. 3-hydroxy-DL-kynurenine (2 x 10(-3) M) and 3-hydroxyanthranilic acid (10(-3) M) inhibited Na,K-ATPase activity by 27% and 30% respectively. Only 3-hydroxy-DL-kynurenine had a demonstrable effect on 86Rb uptake. It is concluded that, in contrast to findings in the amphibian lens, metabolites of tryptophan have minimal or no detrimental effects upon rabbit lens electrolyte balance under the in vitro conditions of these experiments. However, this does not rule out a long term effect of these compounds should they accumulate in the lens.

摘要

研究了色氨酸及其三种主要代谢产物对兔晶状体电解质平衡的影响。即使在3×10⁻³M色氨酸浓度下，经20小时孵育后，色胺和黄尿酸对晶状体钠、钾和钙含量均无影响。在2×10⁻³M 3-羟基-DL-犬尿氨酸和10⁻³M羟基邻氨基苯甲酸中孵育20小时，可引起晶状体钠和钾含量发生微小但显著的变化。3×10⁻³M色氨酸对晶状体Na,K-ATP酶活性无影响。色胺在3×10⁻³M时可使Na,K-ATP酶活性略有降低，但在10⁻³M时无此作用。2×10⁻³M 3-羟基-DL-犬尿氨酸和10⁻³M羟基邻氨基苯甲酸分别使Na,K-ATP酶活性抑制27%和30%。只有3-羟基-DL-犬尿氨酸对⁸⁶Rb摄取有明显作用。得出的结论是，与在两栖类晶状体中的发现相反，在这些实验的体外条件下，色氨酸代谢产物对兔晶状体电解质平衡的影响极小或无不利影响。然而，这并不排除这些化合物在晶状体中蓄积时产生的长期影响。