Transmembrane exchange of chloride with bicarbonate ion in mammalian red blood cells: evidence for a sulphonamide‐sensitive "carrier".
Transmembrane exchange of chloride with bicarbonate ion in mammalian red blood cells: evidence for a sulphonamide‐sensitive "carrier".
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哺乳动物红细胞中氯离子与碳酸氢根离子的跨膜交换：磺胺敏感“载体”的证据。
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发表时间：
1975
期刊：
影响因子：
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通讯作者：
F. Sola
中科院分区：
文献类型：
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作者：
J. Cousin;R. Motais;F. Sola
1. 众所周知，悬浮在等渗 NH4Cl 溶液中的红细胞会膨胀，因为 NH3 的渗透会诱导 Cl-o 和 OH-i（或 HCO3-i）之间的跨膜交换。因此，膨胀速率取决于跨膜交换的速度和可用于交换的阴离子的量。 2. 在不含 CO2 的介质中进行的实验表明，OH-离子的渗透性很差，而 HCO3-的渗透性非常高。因此，肿胀速率很大程度上取决于细胞内 HCO3 浓度。在这种情况下，众所周知的磺胺类药物对肿胀的抑制作用可以被解释为由于该药物对细胞内碳酸酐酶的抑制作用，并且迄今为止一直如此。然而，这种抑制作用也可能是由于药物对跨膜交换的直接作用所致。这可以解释为什么在完全碳酸酐酶抑制的条件下，我们已经证明对膨胀的抑制远非最大。 3. 使用苯甲酰胺 (Cl 11,366)、Cl 13,580 和乙恶唑酰胺获得了碳酸酐酶抑制剂对 Cl- 与 HCO3- 跨膜交换的影响的直接实验证据。然而，令人惊讶的是，乙酰唑酰胺（Diamox）不会影响跨膜交换过程。 4. 磺胺类药物对 HCO3 转运过程的抑制作用是根据药物与 HCO3 和有机阴离子共有的转运系统的相互作用来讨论的。
1. It is well known that red blood cells suspended in isotonic NH4Cl solution swell because penetration of NH3 induces a transmembrane exchange between Cl‐o and OH‐i(or HCO3‐i). The rate of swelling thus depends on the speed of the transmembrane exchanges and on the amount of anions available for exchange. 2. It has been demonstrated in experiments carried out in a CO2‐free medium that OH‐ions are poorly permeating whereas the permeability for HCO3‐is very high. Thus the rate of swelling is largely dependent on the intracellular HCO3‐concentration. In this context the well‐known inhibitory effect of sulphonamides upon swelling can be interpreted, and always has been until now, as being due to the inhibitory action of the drug on the intracellular carbonic anhydrase. However, this inhibitory effect could also result from a direct action of the drug on the transmembrane exchange; it would explain why under conditions of total carbonic anhydrase inhibition we have shown that the inhibition of swelling is far from maximal. 3. A direct experimental evidence of such an effect of carbonic anhydrase inhibitors on the transmembrane exchange of Cl‐with HCO3‐ was obtained with benzolamide (Cl 11,366), Cl 13,580 and ethoxzolamide. Surprisingly enough, however, acetazolamide (Diamox) does not affect the transmembrane exchange process. 4. The inhibitory effect of sulphonamides on HCO3‐transport process is discussed in terms of an interaction of the drug with a transport system common to HCO3‐ and organic anions.