N‐ethylmaleimide‐inhibited electrogenic K+ secretion in the ampulla of the frog semicircular canal.
N‐ethylmaleimide‐inhibited electrogenic K+ secretion in the ampulla of the frog semicircular canal.
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N-乙基马来酰亚胺抑制青蛙半规管壶腹部的电动 K+ 分泌。
DOI：
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
C. Amiel
中科院分区：
文献类型：
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作者：
E. Ferrary;C. Bernard;O. Oudar;A. Loiseau;O. Sterkers;C. Amiel
1.用不同药理学抑制剂制备离体半规管，研究K+分泌到内淋巴的机制。进行三个 5 或 30 分钟的周期，第一个周期作为对照，第二个周期在向心尖或基底外侧沐浴液中添加药物的情况下进行，第三个周期作为恢复。在每个周期开始和结束时对心尖液进行取样，记录跨上皮电位，测量Na+、K+和Cl-浓度以及K+流出（以86Rb+作为示踪剂）并计算K+通量。 2.当上皮两侧均沐浴有类外淋巴液时，上皮吸收Na+，分泌K+，产生管腔正电位。 3. ATPase 抑制剂哇巴因（10(‐5) 和 10(‐3) M）和 N-乙基马来酰亚胺（10(‐4) 和 10(‐3) M）添加到基底外侧液中时会抑制电 K+ 分泌。 N-乙基马来酰亚胺 (10(‐3) M) 在 5 分钟内应用于根尖液，使 K+ 流入量减少 43%，跨上皮电位减少 66%。其他 ATP 酶抑制剂，骆驼蓬碱 (10(‐3) M)、奥美拉唑 (10(‐4) M)、钒酸盐（10(‐4) M 和 10(‐3) M)、N,N'-二环己基碳二亚胺 (DCC，10(‐5) M)、7-氯-4-硝基苯并-2-氧杂-1,3-二唑 (NBD-Cl，5 x当将 10(‐6) M 和 5 x 10(‐5) M) 和巴弗洛霉素 (10(‐7) M) 添加到根尖液中时，它们不会影响 K+ 转运或跨上皮电位。 4. Na(+)-K(+)-Cl-协同转运蛋白抑制剂布美他尼添加到基底外侧溶液中时，会降低跨上皮电位和 K+ 转运，但添加到顶端溶液中则不会。在 10(‐6) M 时，布美他尼最大程度地减少了 K+ 流入约 60%。 5. K+通道阻滞剂、奎宁 (10(‐4) M)、TEA (5 x 10(‐3) M) 添加到顶端溶液中，并且将钡 (2 x 10(‐3) M) 添加到顶端或基底外侧溶液中，不会影响 K+ 转运和跨上皮电位。 6. 添加到顶端和基底外侧溶液中的碳酸酐酶抑制剂乙酰唑胺（10(‐3) M）不会影响 K+ 转运和跨上皮电位。 7. 结论是，在半规管壶腹中，由 Na+、K(+)-ATP 酶供能的基底外侧 Na(+)-K(+)-Cl- 协同转运蛋白参与了 60% 的 K+ 分泌至内淋巴的过程。产生电的 K+ 转运部分依赖于可能位于顶端质膜或细胞内的 N-乙基马来酰亚胺敏感蛋白。
1. The mechanisms of K+ secretion into endolymph were studied on a preparation of isolated semicircular canal with different pharmacological inhibitors. Three periods of 5 or 30 min were performed, the first as control, the second in the presence of the drugs added to the apical or the basolateral bathing solution, and the third as recovery. Apical fluid was sampled at the beginning and the end of each period, transepithelial potential was recorded, Na+, K+, and Cl‐ concentrations, and K+ efflux, with 86Rb+ as a tracer, were measured and K+ fluxes were calculated. 2. When both sides of the epithelium were bathed with perilymph‐like solution, the epithelium absorbed Na+, secreted K+, and generated a lumen positive potential. 3. The ATPases inhibitors, ouabain (10(‐5) and 10(‐3) M) and N‐ethylmaleimide (10(‐4) and 10(‐3) M) inhibited the electrogenic K+ secretion when added to the basolateral fluid. N‐ethylmaleimide (10(‐3) M) applied to the apical fluid during a 5 min period decreased the K+ influx by 43% and the transepithelial potential by 66%. Other ATPase inhibitors, harmaline (10(‐3) M), omeprazole (10(‐4) M), vanadate (10(‐4) M and 10(‐3) M), N,N'‐dicyclohexylcarbodiimide (DCC, 10(‐5) M), 7‐chloro‐4‐nitrobenz‐2‐oxa‐1,3‐diazole (NBD‐Cl, 5 x 10(‐6) M and 5 x 10(‐5) M), and bafilomycin (10(‐7) M) did not affect the K+ transport nor the transepithelial potential when they were added to the apical fluid. 4. The Na(+)‐K(+)‐Cl‐ co‐transporter inhibitor, bumetanide, decreased both the transepithelial potential and the K+ transport when added to the basolateral solution but not to the apical one. At 10(‐6) M, bumetanide maximally decreased the K+ influx by about 60%. 5. K+ channel blockers, quinine (10(‐4) M), TEA (5 x 10(‐3) M), added to the apical solution and barium (2 x 10(‐3) M) added to either the apical or the basolateral solutions, did not affect the K+ transport and the transepithelial potential. 6. The carbonic anhydrase inhibitor acetazolamide (10(‐3) M) added to both apical and basolateral solutions did not affect the K+ transport and the transepithelial potential. 7. It is concluded that, in the ampulla of the semicircular canal, a basolateral Na(+)‐K(+)‐Cl‐ co‐transporter energized by the Na+, K(+)‐ATPase was involved for 60% in the K+ secretion into endolymph. The electrogenic K+ transport would partly depend on a N‐ethylmaleimide‐sensitive protein possibly located at the apical plasma membrane or intracellularly.
DOI：
10.1152/ajprenal.1987.253.4.f613
发表时间：
1987-10
期刊：
The American journal of physiology
影响因子：
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作者：
N. Marcus;D. C. Marcus
通讯作者：
N. Marcus;D. C. Marcus
沙鼠椭圆囊非感觉区对 Cl- 的跨上皮电反应。
DOI：
10.1016/0005-2736(89)90454-9
发表时间：
1989
期刊：
Biochimica et biophysica acta
影响因子：
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作者：
Marcus,DC;Marcus,NY
通讯作者：
Marcus,NY
兔子 CCD 的 K 和 Rb 传输：Rb 降低 K 电导和 Na 传输。
DOI：
10.1152/ajprenal.1989.257.1.f43
发表时间：
1989
期刊：
The American journal of physiology
影响因子：
--
作者：
Warden,DH;Hayashi,M;Schuster,VL;Stokes,JB
通讯作者：
Stokes,JB