Thiol-dependent K:Cl transport in sheep red cells: VIII. Activation through metabolically and chemically reversible oxidation by diamide.
Thiol-dependent K:Cl transport in sheep red cells: VIII. Activation through metabolically and chemically reversible oxidation by diamide.
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绵羊红细胞中硫醇依赖性 K:Cl 转运：VIII。
DOI：
10.1007/bf01872833
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Lauf,PK
中科院分区：
文献类型：
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作者：
Lauf,PK
在低钾(LK)和高钾(HK)绵羊红细胞中，巯基(SH)氧化剂联胺以浓度依赖的方式激活抗(OR)、依赖于氯的钾流动，这由NO_3或甲烷磺酸(CH_3SO_3)取代氯或氯进入介质中的零转移钾流出速率确定。联胺不改变OR-Na向胆碱氯的外流。细胞内80%的谷胱甘肽(GSH)被氧化成其二硫化物GSSG后，对K的外流有联胺效应。在GSH的代谢恢复过程中，钾外流的刺激被完全逆转，这一过程依赖于暴露于联胺的时间和浓度。二硫苏糖醇(DTT)可完全逆转联胺对K：CL转运体和GSH的作用。联胺明显氧化由N-乙基马来酰亚胺(NEM)烷基化的相同的SH基团(Lauf，P.K.1983，《膜生物》73：237-246)。与NEM一样，联胺激活的K：CL在LK细胞中的转运是在HK细胞中的数倍，这种作用可被抗L1抗体部分抑制，L1抗体是已知的抑制OR K通量的同种异体抗体。
The sulfhydryl (SH) oxidant diamide activated in a concentration-dependent manner ouabain-resistant (OR), Cl-dependent K flux in both low potassium (LK) and high potassium (HK) sheep red cells as determined from the rate of zero-transK efflux into media with Cl or Cl replaced by NO3or methane sulfonate (CH3SO3). Diamide did not alter the OR Na efflux into choline Cl. The diamide effect on K efflux appeared after 80% of cellular glutathione (GSH) was oxidized to GSSG, its disulfide. The stimulation of K efflux was completely reversed during metabolic restitution of GSH, a process that depended on the length of exposure to and the concentration of diamide. The action of diamide on both the K∶Cl transporter and GSH was also fully reversed by the reducing agent dithiothreitol (DTT). Diamide apparently oxidized the same SH groups alkylated by N-ethylmaleimide (NEM) (Lauf, P.K. 1983.J. Membrane Biol..73:237–246). Like NEM, diamide activated K∶Cl transport several-fold more in LK cells than in HK cells, and the effect on LK cells was partially inhibited by anti-L1, the allo-antibody known to inhibit OR K fluxes.