Faber S, Lang H J, Hock F J, Schölkens B A, Mutschler E
Hoechst Marion Roussel Deutschland GmbH, Bad Soden, Germany.
Cell Physiol Biochem. 1998;8(4):202-11. doi: 10.1159/000016283.
Regulation of intracellular pH (pHi) was studied in cultured bovine aortic endothelial cells, an important cell system for cardiovascular research. Suspended cells were acidified by the NH4Cl prepulse technique as well as by exposure to CO2/HCO3-. Subsequent rates of pHi recovery were monitored using the fluorescent dye 2',7'-bis(2-carboxyethyl)-5-(6)-carboxyfluorescein (BCECF). In HCO3(-)-free solutions, an EIPA-sensitive, Na+-dependent mechanism fully accounted for realkalinization, namely the Na+/H+ exchanger (NHE). In the presence of HCO3-, an additional acid efflux mechanism was found. This one was dependent on Na+ and intracellular Cl-, EIPA-insensitive but DIDS-sensitive, and therefore represented a Na+-dependent Cl-/HCO3- exchanger (NCBE). In summary, two acid-extruding mechanisms were identified in bovine aortic endothelial cells: NHE and NCBE.
在培养的牛主动脉内皮细胞（心血管研究中的一种重要细胞系统）中研究了细胞内pH值（pHi）的调节。悬浮细胞通过NH4Cl预脉冲技术以及暴露于CO2/HCO3-而被酸化。随后使用荧光染料2'，7'-双（2-羧乙基）-5-（6）-羧基荧光素（BCECF）监测pHi恢复的速率。在无HCO3（-）的溶液中，一种对EIPA敏感、依赖Na+的机制完全解释了再碱化过程，即Na+/H+交换体（NHE）。在有HCO3-存在的情况下，发现了另一种酸外排机制。这种机制依赖于Na+和细胞内Cl-，对EIPA不敏感但对DIDS敏感，因此代表一种依赖Na+的Cl-/HCO3-交换体（NCBE）。总之，在牛主动脉内皮细胞中鉴定出了两种酸排出机制：NHE和NCBE。
