Evidence for apical sodium proton exchange in macula densa cells.
Evidence for apical sodium proton exchange in macula densa cells.
复制标题
致密斑细胞顶端钠质子交换的证据。
DOI：
10.1038/ki.1995.114
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发表时间：
1995
影响因子：
19.6
通讯作者：
Bell,PD
中科院分区：
文献类型：
--
作者：
Fowler,BC;Chang,YS;Laamarti,A;Higdon,M;Lapointe,JY;Bell,PD
Evidence for apical sodium proton exchange in macula densa cells. These studies were performed to determine if changes in luminal sodium chloride concentration ([NaCl]) might alter macula densa intracellular pH. Isolated thick ascending limbs with attached glomeruli were bathed in a 150 mMNaCl Ringer's solution and perfusedin vitrowith a 25 mMNaCl solution; N-methyl-D-glucamine cyclamate was used to substitute for NaCl. Macula densa cells were loaded with BCECF and intracellular pH was monitored using a microscope based-dual excitation photometer system. Control intracellular pH for all experiments in which tubules were initially perfused with 25 mMNaCl averaged 7.22 ± 0.06; N = 28. Increasing luminal [NaCl] from 25 to 150 mMelevated macula densa pH by 0.15 ± 0.03 (N = 6; P < 0.05) while increasing just luminal [Na] from 25 to 150 mMalkalinized macula densa cells by 0.17 ± 0.05 (N = 6; P < 0.05). In addition, there was a highly significant linear relationship between luminal [Na] and intracellular pH between 25 and 150 mMNaCl. Other studies were performed to assess the effects of amiloride, an inhibitor of Na:H exchange, on macula densa intracellular pH. Addition of amiloride, to the 25 mMNaCl perfusate acidified macula densa cells by 0.09 ± 0.03 (N = 6; P < 0.001) and significantly attenuated the increase in pH obtained when luminal [NaCl] was raised from 25 to 150 mM. Other studies evaluated the effects of inhibition of Na:2Cl:K cotransport on macula densa pH. Furosemide (50 µm) alkalinized macula densa pH by 0.11 ± 0.02 (N = 5; P < 0.01) in the presence of 25 mMNaCl in the lumen whereas amiloride entirely reversed the furosemide-induced alkaninization in these cells. These results demonstrate that changes in either luminal [NaCl] or furosemide-sensitive NaCl transport can alter macula densa intracellular pH presumably by varying the Na gradient across the apical membrane. The results of these studies are consistent with the existence of an apical Na:H antiporter in macula densa cells.
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影响因子：
18.2
作者：
W. Boron
通讯作者：
W. Boron
影响因子：
--
作者：
GOOD, DW
通讯作者：
GOOD, DW
肾小管-肾小球反馈反应与灌注液低渗性之间的关系。
影响因子：
19.6
作者：
Bell,PD;Navar,LG
通讯作者：
Navar,LG
致密斑细胞中鲁米那氯化物激活 Na:2Cl:K 共转运。
影响因子：
19.6
作者：
Lapointe,JY;Laamarti,A;Hurst,AM;Fowler,BC;Bell,PD
通讯作者：
Bell,PD
Na /H 逆向转运蛋白在肾近曲小管上皮细胞中的不对称分布。
DOI：
10.1016/s0021-9258(17)43943-3
发表时间：
1983
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
H. Ives;V. Yee;D. Warnock
通讯作者：
D. Warnock