Efficiency of primary saliva secretion: an analysis of parameter dependence in dynamic single-cell and acinus models, with application to aquaporin knockout studies.
Efficiency of primary saliva secretion: an analysis of parameter dependence in dynamic single-cell and acinus models, with application to aquaporin knockout studies.
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DOI：
10.1007/s00232-011-9413-3
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发表时间：
2012-01
影响因子：
2.4
通讯作者：
Crampin, Edmund J.
中科院分区：
文献类型：
--
作者：
Maclaren, Oliver J.;Sneyd, James;Crampin, Edmund J.
关键词：
唾液腺的分泌是由渗透作用驱动的，通过主动离子转运在管腔、细胞和囊体之间建立渗透梯度。我们考虑了一个动态模型的主动驱动的初级唾液分泌，并使用奇异摄动方法和缩放的假设，以减少模型。我们的分析表明，等渗分泌是最有效的分泌制度，这适用于单个分离的细胞和多个细胞组装成一个腺泡。对于典型的参数变化，我们排除了任何显着的协同效应，对总水分泌的腺泡排列的细胞约一个单一的共享管腔。实现等渗分泌的条件被认为是，我们推导出一个表达式之间的浓度梯度的铯和管腔尺度与水和氯离子的运输参数。水通道蛋白敲除研究的背景下，我们的分析和进一步研究使用不同的膜透水性的运输效率的模拟。我们的结论是，最近声称水通道蛋白敲除研究可以解释为一个简单的渗透机制的证据不支持我们的工作。我们获得的许多结果是独立的具体转运细节，我们的分析可以很容易地扩展到适用于模型，使用其他提出的离子机制的唾液分泌。
Secretion from the salivary glands is driven by osmosis following the establishment of osmotic gradients between the lumen, the cell and the interstitium by active ion transport. We consider a dynamic model of osmotically-driven primary saliva secretion, and use singular perturbation approaches and scaling assumptions to reduce the model. Our analysis shows that isosmotic secretion is the most efficient secretion regime, and that this holds for single isolated cells and for multiple cells assembled into an acinus. For typical parameter variations, we rule out any significant synergistic effect on total water secretion of an acinar arrangement of cells about a single shared lumen. Conditions for the attainment of isosmotic secretion are considered, and we derive an expression for how the concentration gradient between the interstitium and the lumen scales with water and chloride transport parameters. Aquaporin knockout studies are interpreted in the context of our analysis and further investigated using simulations of transport efficiency with different membrane water permeabilities. We conclude that recent claims that aquaporin knockout studies can be interpreted as evidence against a simple osmotic mechanism are not supported by our work. Many of the results that we obtain are independent of specific transporter details, and our analysis can be easily extended to apply to models that use other proposed ionic mechanisms of saliva secretion.
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影响因子：
2
作者：
LAUGER, P;APELL, HJ
通讯作者：
APELL, HJ
影响因子：
4.8
作者：
Ma, TH;Song, YL;Verkman, AS
通讯作者：
Verkman, AS
DOI：
10.1073/pnas.95.6.2991
发表时间：
1998-03-17
影响因子：
11.1
作者：
Dobbs, LG;Gonzalez, R;Verkman, AS
通讯作者：
Verkman, AS
DOI：
10.1085/jgp.48.1.15
发表时间：
1964-09
期刊：
The Journal of general physiology
影响因子：
--
作者：
DIAMOND JM
通讯作者：
DIAMOND JM
影响因子：
2.4
作者：
Mathias, RT;Wang, H
通讯作者：
Wang, H