蛙胃营养膜中存在简单氯离子传导途径的进一步证据。

Further evidence for a simple Cl- conductance pathway in nutrient membrane of frog stomach.

作者信息

Schwartz M, Holloman T L, Zhang J Y, Carrasquer G

机构信息

Department of Physics, University of Louisville, KY 40292.

出版信息

Biochim Biophys Acta. 1991 Feb 11;1062(1):113-5. doi: 10.1016/0005-2736(91)90342-6.

DOI:10.1016/0005-2736(91)90342-6

PMID:1998704

Abstract

A decrease in nutrient Cl- increases the negativity of the nutrient relative to the secretory side. It seemed possible that Cl- transport could result from a neutral Cl- mechanism in the nutrient membrane coupled to a simple Cl- conductance pathway in the secretory membrane. Experiments in HCO3(-)-free, K(+)-free and Na(+)-free solutions in both bathing media gave for a 10-fold change in nutrient Cl- a PD change of 9.5 mV. Similar experiments with 0.5 mM DIDS in the nutrient solution gave for a 10-fold change in nutrient Cl- a PD change of 7.9 mV. These experiments eliminated a neutral Cl(-)-HCO3- exchanger, a NaCl and a KCl symport. Thus the change in PD could best be explained by a simple Cl- conductance in the nutrient membrane.

摘要

营养物中氯离子的减少会增加营养物相对于分泌侧的负电性。似乎氯离子转运可能源于营养物膜中的中性氯离子机制与分泌膜中简单的氯离子电导途径相耦合。在两种灌流介质的无HCO3(-)、无K(+)和无Na(+)溶液中进行的实验表明，营养物氯离子浓度变化10倍时，跨膜电位变化9.5 mV。在营养液中加入0.5 mM DIDS进行的类似实验表明，营养物氯离子浓度变化10倍时，跨膜电位变化7.9 mV。这些实验排除了中性Cl(-)-HCO3-交换体、NaCl和KCl同向转运体。因此，跨膜电位的变化最能由营养物膜中简单的氯离子电导来解释。