Omerovic A, Chen S J, Leonard J P, Kelso S R
Department of Biological Sciences, University of Illinois at Chicago 60607, USA.
J Recept Signal Transduct Res. 1995 Jul;15(6):811-27. doi: 10.3109/10799899509049859.
We have examined the effects of oxidizing and reducing agents on a number of subtypes of N-methyl-D-aspartate (NMDA) receptors expressed in Xenopus oocytes. Oocytes were injected with cRNA for the zeta 1 subunit from mouse to express homomeric receptors or with zeta 1 in combination with either epsilon 1, epsilon 2, epsilon 3 or epsilon 4 subunits to express heteromeric receptors. All heteromeric combinations resulted in receptors that were affected by the redox reagents, dithiothreitol (DTT) and 5-5-dithio-bis-2-nitrobenzoic acid (DTNB). However, the effects on the small currents from homomeric receptors were quite variable. The zeta 1/epsilon 3 combination showed a greater enhancement by DTT than any of the other combinations. All four receptors expressed showed both a component of persistent potentiation and a slowly reversible component. The reversible component was largest for zeta 1/epsilon 3. Additional experiments were done with S-nitrosocysteine (SNOC), a nitric oxide donor that may affect NMDA receptors by oxidation. SNOC had transient effects on the four heteromeric subunit combinations. The different sensitivities of particular subunit combinations may have pharmacological and clinical significance.
我们研究了氧化还原剂对非洲爪蟾卵母细胞中表达的多种N-甲基-D-天冬氨酸（NMDA）受体亚型的影响。向卵母细胞注射小鼠ζ1亚基的cRNA以表达同聚体受体，或注射ζ1并与ε1、ε2、ε3或ε4亚基结合以表达异聚体受体。所有异聚体组合产生的受体均受氧化还原试剂二硫苏糖醇（DTT）和5,5'-二硫代双（2-硝基苯甲酸）（DTNB）的影响。然而，同聚体受体产生的小电流所受影响变化很大。ζ1/ε3组合受DTT的增强作用比其他任何组合都更大。所表达的所有四种受体均显示出持续增强成分和缓慢可逆成分。ζ1/ε3的可逆成分最大。我们还使用一氧化氮供体亚硝基半胱氨酸（SNOC）进行了额外实验，SNOC可能通过氧化作用影响NMDA受体。SNOC对四种异聚体亚基组合有短暂影响。特定亚基组合的不同敏感性可能具有药理学和临床意义。
