Secretion of tetraethylammonium by proximal tubules of rabbit kidneys.
Secretion of tetraethylammonium by proximal tubules of rabbit kidneys.
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兔肾近端肾小管分泌四乙铵。
DOI：
10.1152/ajprenal.1983.245.2.f238
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
F. Roch
中科院分区：
文献类型：
--
作者：
C. Schäli;L. Schild;J. Overney;F. Roch
在兔肾近端小管的灌注和非灌注分离 S1、S2 和 S3 段中研究了四乙铵 (TEA) 的分泌转运。在灌注的肾小管中，跨上皮净分泌通量和在非灌注的肾小管中，TEA细胞摄取是饱和的（灌注的S2段中Km = 67 microM，Vmax = 2,480 fmol X min-1 X mm-1），能量依赖性，并被甲哌苯尼醇抑制。在 TEA 浓度为 40 µM 的浴液中，TEA 的净分泌通量（J b 导致 j TEA）对于三个片段而言是不同的，并且按照 S1 大于 S2 大于 S3 的顺序下降。离开肾小管的灌注液中的 TEA 浓度约为浴液中的两倍，细胞内 TEA 浓度约为浴液中的 40 倍。在非灌注节段（孵育介质中为 40 microM TEA）中，TEA 组织水与介质的比率达到 100。因此，在这三个节段中，穿过管周膜积累 TEA 的能力相似，但跨上皮分泌通量显着不同。这三个节段之间的分泌率差异可能是由于管腔膜渗透性的差异造成的。
The secretory transport of tetraethylammonium (TEA) was investigated in perfused and nonperfused isolated S1, S2, and S3 segments of proximal tubules from rabbit kidneys. In the perfused tubules the transepithelial net secretory flux and in nonperfused tubules the TEA cellular uptake were saturable (Km = 67 microM, Vmax = 2,480 fmol X min-1 X mm-1 in perfused S2 segments), energy dependent, and inhibited by mepiperphenidol. The net secretory flux of TEA (J b leads to j TEA) at a bath TEA concentration of 40 microM differed for the three segments and decreased in the order S1 greater than S2 greater than S3. The concentration of TEA in the perfusate leaving the tubule was approximately twice as great and the intracellular TEA concentration approximately 40 times as great as that in the bath. In nonperfused segments (40 microM TEA in the incubation medium) the TEA tissue water-to-medium ratio reached 100. In the three segments the ability to accumulate TEA across the peritubular membrane, thus, was similar, but the transepithelial secretory flux differed significantly. The differences in secretory rate between the three segments presumably result from differences in the luminal membrane permeability.