rOCT2 is a basolateral potential-driven carrier, not an organic cation/proton exchanger.
rOCT2 is a basolateral potential-driven carrier, not an organic cation/proton exchanger.
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rOCT2 是基底外侧电位驱动的载体，而不是有机阳离子/质子交换剂。
DOI：
10.1152/ajprenal.1999.277.6.f890
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Pritchard,JB
中科院分区：
文献类型：
--
作者：
Sweet,DH;Pritchard,JB
在表达大鼠肾脏（rOCT2）有机阳离子转运体（OCT） 2的xenopusoocytes和MDCK细胞中，系统地评估了介导四乙基铵（TEA）运输的驱动力。在注射rOCT2 crna的卵母细胞中，[14C]TEA的摄取是饱和的，估计米切里斯常数（Km）为393 μM，并被有机阳离子特异性抑制。此外，TEA摄取表现出两种不同的成分，一种是电位敏感的，另一种是pH敏感的。当膜电位不变时，TEA的摄取基本不受培养基pH变化的影响；当卵母细胞膜去极化（K+in = out = 102.5 mM，加上valinomycin）时，降低外部培养基pH显著降低TEA的摄取。与摄取的潜在敏感性一致，电生理分析显示，在添加TEA后，注射roct2的卵母细胞中出现了正电荷向卵母细胞的移动。为了进一步评估pH效应的性质和评估rOCT2在肾上皮中的特性，将rOCT2引入MDCK细胞。稳定转染的单细胞克隆（MDCK-rOCT2）表现出介导的、电位敏感的、ph敏感的TEA摄取（Km= 48 μM）。外用（反式）四甲基铵刺激预加载MDCK-rOCT2细胞的TEA外排，但H+（外用pH 5.4）抑制其外排。外部H+的作用是调节roct2介导的转运。因此，rOCT2是一种电位驱动的转运体，而不是有机阳离子/H+交换体，这与肾脏有机阳离子分泌的基底外侧进入步骤的生理作用一致。
The driving forces mediating tetraethylammonium (TEA) transport were systematically assessed inXenopusoocytes and MDCK cells expressing organic cation transporter (OCT) 2 cloned from rat kidney (rOCT2). In rOCT2 cRNA-injected oocytes, uptake of [14C]TEA was saturable, with an estimated Michaelis constant (Km) of 393 μM, and was specifically inhibited by organic cations. Furthermore, TEA uptake demonstrated two distinct components, one that was potential sensitive and one that was pH sensitive. When membrane potential was intact, TEA uptake was largely unaffected by changes in medium pH; when the oocyte membrane was depolarized (K+in = out = 102.5 mM, plus valinomycin), decreasing external medium pH significantly reduced TEA uptake. Consistent with the potential sensitivity of uptake, electrophysiological analysis of rOCT2-injected oocytes demonstrated movement of positive charge into the oocyte upon TEA addition. To further evaluate the nature of the pH effect and assess the properties of rOCT2 in a renal epithelium, rOCT2 was introduced into MDCK cells. A stably transfected single cell clone (MDCK-rOCT2) showed mediated, potential-sensitive, pH-sensitive TEA uptake (Km= 48 μM). TEA efflux from preloaded MDCK-rOCT2 cells was stimulated by externally applied (trans) tetramethylammonium but wastrans-inhibited by H+(external pH 5.4). The effect of external H+was to modulate rOCT2-mediated transport. Thus rOCT2 is a potential-driven transporter, not an organic cation/H+exchanger, consistent with a physiological role in the basolateral entry step in renal organic cation secretion.
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影响因子：
21.1
作者：
J. M. Ford;W. Hait
通讯作者：
J. M. Ford;W. Hait
肾上皮 LLC-PK1 细胞顶端有机阳离子转运蛋白的一级结构和功能表达*
DOI：
10.1074/jbc.272.16.10408
发表时间：
1997
期刊：
The Journal of Biological Chemistry
影响因子：
--
作者：
D. Gründemann;J. Babin;F. Martel;N. Örding;A. Schmidt;E. Schömig
通讯作者：
E. Schömig
肾脏有机阳离子转运蛋白的结构和功能。
DOI：
10.1152/physiologyonline.1998.13.1.11
发表时间：
1998
期刊：
News in physiological sciences : an international journal of physiology produced jointly by the International Union of Physiological Sciences and the American Physiological Society
影响因子：
--
作者：
H. Koepsell;A. Busch;V. Gorboulev;P. Arndt
通讯作者：
P. Arndt
源自兔肺和肝 cDNA 的多种形式的细胞色素 P-450 同工酶 2 的一级结构。
影响因子：
3.6
作者：
R. Gasser;M. Negishi;R. Philpot
通讯作者：
R. Philpot
影响因子：
15
作者：
Voinov, Maxim A.;Pagan, Jason O. Sosa;Smirnov, Alex I.
通讯作者：
Smirnov, Alex I.