Macula densa Na(+)/H(+) exchange activities mediated by apical NHE2 and basolateral NHE4 isoforms.
Macula densa Na(+)/H(+) exchange activities mediated by apical NHE2 and basolateral NHE4 isoforms.
复制标题
致密斑 Na( )/H( ) 交换活动由顶端 NHE2 和基底外侧 NHE4 亚型介导。
DOI：
10.1152/ajprenal.2000.278.3.f452
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Bell,PD
中科院分区：
文献类型：
--
作者：
Peti-Peterdi,J;Chambrey,R;Bebok,Z;Biemesderfer,D;StJohn,PL;Abrahamson,DR;Warnock,DG;Bell,PD
Functional and immunohistochemical studies were performed to localize and identify Na+/H+exchanger (NHE) isoforms in macula densa cells. By using the isolated perfused thick ascending limb with attached glomerulus preparation dissected from rabbit kidney, intracellular pH (pHi) was measured with fluorescence microscopy by using 2′,7′-bis-(2-carboxyethyl)-5-(and -6) carboxyfluorescein. NHE activity was assayed by measuring the initial rate of Na+-dependent pHirecovery from an acid load imposed by prior lumen and bath Na+removal. Removal of Na+from the bath resulted in a significant, DIDS-insensitive, ethylisopropyl amiloride (EIPA)-inhibitable decrease in pHi. This basolateral transporter showed very low affinity for EIPA and Hoechst 694 (IC50= 9.0 and 247 μM, respectively, consistent with NHE4). The recently reported apical NHE was more sensitive to inhibition by these drugs (IC50= 0.86 and 7.6 μM, respectively, consistent with NHE2). Increasing osmolality, a known activator of NHE4, greatly stimulated basolateral NHE. Immunohistochemical studies using antibodies against NHE1–4 peptides demonstrated expression of NHE2 along the apical and NHE4 along the basolateral, membrane, whereas NHE1 and NHE3 were not detected. These results suggest that macula densa cells functionally and immunologically express NHE2 at the apical membrane and NHE4 at the basolateral membrane. These two isoforms likely participate in Na+transport, pHi, and cell volume regulation and may be involved in tubuloglomerular feedback signaling by these cells.
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分离和灌注的致密黄斑的直接可视化。
DOI：
10.1152/ajprenal.1985.248.6.f890
发表时间：
1985
期刊：
The American journal of physiology
影响因子：
--
作者：
Kirk,KL;Bell,PD;Barfuss,DW;Ribadeneira,M
通讯作者：
Ribadeneira,M
影响因子：
--
作者：
BIEMESDERFER, D;REILLY, RF;ARONSON, PS
通讯作者：
ARONSON, PS
兔外髓集合管内条顶膜和基底外侧膜 H 挤压机制。
DOI：
10.1152/ajprenal.1990.259.4.f628
发表时间：
1990
期刊：
The American journal of physiology
影响因子：
--
作者：
Hays,SR;Alpern,RJ
通讯作者：
Alpern,RJ
兔 S3 近曲小管中的基底外侧膜 Na /H 逆向转运、Na /碱基共转运和 Na 不依赖的 Cl-/碱基交换。
DOI：
10.1172/jci113925
发表时间：
1989
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
I. Kurtz
通讯作者：
I. Kurtz
影响因子：
3.2
作者：
MCLEAN, IW;NAKANE, PK
通讯作者：
NAKANE, PK