Control of epithelial Cl(-) secretion by basolateral osmolality in the euryhaline teleost Fundulus heteroclitus.
Control of epithelial Cl(-) secretion by basolateral osmolality in the euryhaline teleost Fundulus heteroclitus.
复制标题
广盐硬骨鱼眼底异斜层基底外侧渗透压对上皮 Cl(-) 分泌的控制。
DOI：
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复制
发表时间：
2000
影响因子：
2.8
通讯作者：
T. Luby
中科院分区：
文献类型：
--
作者：
William S. Marshall;S. Bryson;T. Luby
深盐硬骨鱼能迅速适应盐度变化，并在进入淡水时降低离子分泌速率。将鳉鱼（异阴囊底）从全强度海水转移到淡水中，6小时后血浆[Na(+)]和渗透压大幅降低，24小时后得到纠正。为了在体外模拟这种情况，在眼上皮基底外侧施加20-70 mosmol kg(-)(1)的低渗电击。这种低渗休克以剂量依赖性的方式可逆地降低了短路电流(I（sc)，相当于Cl（-）的分泌速率），40 mosmol kg(-)(1)低渗休克在40分钟内使I（sc）降低了58+/- 4.6%。[NaCl]的类似减少，但添加甘露醇来维持渗透压，没有效果，表明效果纯粹是渗透的。I（sc）的低渗抑制伴随着上皮电导（G(t)）的降低，但上皮传导电位（V(t)）没有显著变化。低渗抑制显然不是由Ca（2+）介导的，因为Ca（2+）耗竭的盐碱、thapsigargin和离子霉素都不能阻断低渗休克产生的I（sc）的减少。这种抑制作用不是通过细胞内环AMP水平的降低来介导的，因为放射免疫法测量的环AMP水平在低渗休克和1.0微mol l(-)(1)可乐定(通过改变细胞内[Ca（2+)]抑制I(sc)）时没有变化，但在1.0微mol l(-)(1)异丙肾上腺素（阳性对照）时显着增加。蛋白酪氨酸激酶抑制剂染料木素(100微摩尔l(-)(1))，而不是它的无活性类似物大豆苷元，在正常渗透压下抑制I(sc)，但在低渗休克后（和可乐定治疗后）产生I（sc）刺激。染料木素和低渗性的抑制作用并不是加在一起的，这表明两种处理对I（sc）的抑制作用是相同的。这些数据与泛盐硬骨鱼适应淡水环境时，细胞肿胀诱导的Cl（-）分泌抑制中酪氨酸磷酸化的Cl（-）转运调节模型一致。
Euryhaline teleost fish adapt rapidly to salinity change and reduce their rate of ion secretion on entry to fresh water. Killifish (Fundulus heteroclitus) transferred from full-strength sea water to fresh water showed large reductions in plasma [Na(+)] and osmolality at 6 h which were corrected by 24 h. To mimic this in vitro, a hypotonic shock of 20-70 mosmol kg(-)(1) was applied on the basolateral side of opercular epithelia. This hypotonic shock reversibly reduced the short-circuit current (I(sc), equivalent to the rate of secretion of Cl(-)) in a dose-dependent fashion, with a 40 mosmol kg(-)(1) hypotonic shock reducing I(sc) by 58+/-4.6 % in 40 min. Similar reductions in [NaCl], but with added mannitol to maintain osmolality, were without effect, indicating that the effect was purely osmotic. Hypotonic inhibition of I(sc) was accompanied by reductions in epithelial conductance (G(t)) but no significant change in transepithelial potential (V(t)). The hypotonic inhibition was apparently not Ca(2+)-mediated because Ca(2+)-depleted salines, thapsigargin and ionomycin all failed to block the reduction in I(sc) produced by hypotonic shock. The inhibition was not mediated via a reduction in intracellular cyclic AMP level because cyclic AMP levels, measured by radioimmunoassay, were unchanged by hypotonic shock and by 1.0 micromol l(-)(1) clonidine (which inhibits I(sc) by changing intracellular [Ca(2+)]) but were increased markedly by 1.0 micromol l(-)(1) isoproterenol, a positive control. The protein tyrosine kinase inhibitor genistein (100 micromol l(-)(1)), but not its inactive analogue daidzein, inhibited I(sc) in normal osmolality but produced a stimulation of I(sc) after hypotonic shock (and after clonidine treatment). The inhibitory effects of genistein and hypotonicity were not additive, suggesting that the same portion of the I(sc) was inhibited by both treatments. These data are consistent with a model for Cl(-) transport regulation involving tyrosine phosphorylation in cell-swelling-induced inhibition of Cl(-) secretion when euryhaline teleosts adapt to fresh water.
影响因子：
33.6
作者：
D. Gadsby;A. Nairn
通讯作者：
D. Gadsby;A. Nairn
酪氨酸磷酸化是调节鲨鱼直肠腺氯离子分泌的新途径。
DOI：
10.1152/ajprenal.1995.269.4.f594
发表时间：
1995
期刊：
The American journal of physiology.
影响因子：
--
作者：
Lehrich,RW;ForrestJr,JN
通讯作者：
ForrestJr,JN
α2-肾上腺素能受体激活肾上皮细胞中的磷脂酶 C。
DOI：
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发表时间：
1996
期刊：
Molecular pharmacology.
影响因子：
--
作者：
Gesek,FA
通讯作者：
Gesek,FA