Effects of ouabain and furosemide on basolateral membrane Na efflux of frog skin.
Effects of ouabain and furosemide on basolateral membrane Na efflux of frog skin.
复制标题
哇巴因和呋塞米对蛙皮肤基底外侧膜钠离子流出的影响。
DOI：
10.1152/ajprenal.1983.245.3.f312
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Helman,SI
中科院分区：
文献类型：
--
作者：
Cox,TC;Helman,SI
Na示踪剂通量的动力学在蛙皮肤的分离上皮细胞中，其中真皮的未搅拌层被删除。22 Na在基底侧溶液（JNa13）中的出现率符合示踪剂累积的单指数，平均t1/2为1.9 min。Na转运池标记的同位素从顶端的解决方案是约40 neq/cm 2的上皮细胞沐浴在氯化物或硫酸盐林格氏溶液。基底外侧到顶端的溶液单向Na通量（JNa31）较低，平均为0.7 microA/cm 2，并在哇巴因处理上皮40分钟后保持较低水平。与电生理学数据一致，哇巴因在10（-4）M时引起基底外侧膜（JNa 23）Na流出的急性抑制（小于1 min），分别降至Cl和SO4 Ringer中浸泡的上皮细胞对照的40.6%和26.7%。尽管呋塞米对对照上皮细胞的钠通量几乎没有或没有一致的影响，但这种药物在哇巴因中毒的上皮细胞中引起了中性、氯依赖性、哇巴因不敏感的钠流出的实质性抑制。有人建议，哇巴因“诱导”的钠转运的中性机制，在基底外侧膜的细胞，是氯离子依赖性和呋塞米敏感。
The kinetics of Na tracer fluxes were reinvestigated in isolated epithelia of frog skin in which the unstirred layers of the corium were removed. The rate of appearance of 22Na in the basolateral solution (JNa13) conformed to a single exponential for tracer buildup with a mean t1/2 of 1.9 min. The Na transport pool labeled isotopically from the apical solution was about 40 neq/cm2 for epithelia bathed in either a chloride or sulfate Ringer solution. Basolateral-to-apical solution unidirectional Na flux (JNa31) was low, averaging 0.7 microA/cm2 and remained low for 40 min of ouabain treatment of the epithelia. In agreement with electrophysiological data, ouabain at 10(-4) M caused an acute inhibition (less than 1 min) of the Na efflux at the basolateral membrane (JNa23), falling to 40.6 and 26.7% of control for epithelia bathed in Cl and SO4 Ringer, respectively. Although furosemide exerted little or no consistent effect on the Na flux of control epithelia, this drug in ouabain-poisoned epithelia caused a substantial inhibition of a neutral, chloride-dependent, ouabain-insensitive Na efflux. It is suggested that ouabain "induces" a neutral mechanism of Na transport at the basolateral membrane of the cells that is chloride dependent and furosemide sensitive.