Oscillations and Waves in a Model of InsP3-Controlled Calcium Dynamics
Oscillations and Waves in a Model of InsP3-Controlled Calcium Dynamics
复制标题
InsP3 控制的钙动力学模型中的振荡和波
DOI：
--
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Yuanhua Tang
中科院分区：
文献类型：
--
作者：
H. Othmer;Yuanhua Tang
各种类型的细胞利用激素、神经递质或生长因子引发的细胞内钙的变化作为第二信使，触发各种细胞内反应，包括收缩、分泌、生长和分化。最早揭示钙反应复杂性的实验之一是Woods等人（1986）的实验，他们研究了肝细胞对抗利尿激素（一种动员细胞内钙的激素）的反应。他们发现，在200 nM到1 μM的激素浓度范围内，刺激会引起细胞内钙浓度的重复峰值，而不是简单地提高钙水平。此外，他们发现，随着激素浓度的提高，尖峰的频率增加，但幅度几乎保持不变。因此，连续分级（模拟）的细胞外激素信号被转换为频率编码的数字信号（钙峰值的数量）。从那时起，类似的动态行为在大量的细胞类型中被发现，并导致钙峰和频率编码必须具有生理作用的建议。由于高钙水平具有细胞毒性，因此有必要维持较低的钙平均浓度，但由于钙通常主要作为其他过程的触发因素，因此暂时高于低平均浓度就足以达到此目的。此外，使用一个大的瞬态增长作为触发器允许使用更清晰的响应阈值，从而更好地识别噪声。Meyer & Stryer（1991）提出了其他可能的优势，但迄今为止，几乎没有确凿的证据表明尖峰效应起着重要的生理作用。
Various types of cells use changes in intracellular calcium triggered by hormones, neurotransmitters or growth factors as a second messenger to trigger a variety of intracellular responses, including contraction, secretion, growth and differentiation. One of the earliest experiments that revealed the complexity of the calcium response is that due to Woods et al.(1986), who studied the response of hepatocytes to vasopressin, a hormone that mobilizes intracellular calcium. They found that over the range of 200 nM to 1 μM in the hormone concentration, stimuli evoke repetitive spikes in the intracellular calcium concentration, rather than simply elevating the level of calcium. Moreover, they found that as the hormone concentration was raised, the frequency of spiking increased, but the amplitude remained nearly constant. Thus the continuously-graded (analog) extracellular hormone signal was converted into a frequency-encoded digital signal (the number of calcium spikes). Similar dynamic behavior has been found in a large number of cell types since then, and has lead to the suggestion that calcium spiking and frequency encoding must have a physiological role. Since high calcium levels are cytotoxic, it is necessary to maintain a low average concentration of calcium, but since calcium frequently serves primarily as a trigger for other processes, a transient elevation above a low mean concentration suffices for this purpose. Moreover, using a large transient increase as the trigger permits the use of a sharper threshold for response, and hence better noise discrimination. Other possible advantages are suggested by Meyer & Stryer (1991), but to date there is little hard evidence that the spiking plays an essential physiological role.
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DOI：
10.1016/s0021-9258(18)71469-5
发表时间：
1989-10
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
T. A. Rooney;E. J. Sass;A. P. Thomas
通讯作者：
T. A. Rooney;E. J. Sass;A. P. Thomas
影响因子：
56.9
作者：
FINCH, EA;TURNER, TJ;GOLDIN, SM
通讯作者：
GOLDIN, SM
肌醇三磷酸和钙对非洲爪蟾卵母细胞内钙振荡升高的影响。
DOI：
--
发表时间：
1990
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
DeLisle,S;Krause,KH;Denning,G;Potter,BV;Welsh,MJ
通讯作者：
Welsh,MJ
影响因子：
56.9
作者：
HAROOTUNIAN, AT;KAO, JPY;TSIEN, RY
通讯作者：
TSIEN, RY
AR42J 细胞内 Ca2+振荡的调节。
DOI：
--
发表时间：
1990
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Zhao,H;Loessberg,PA;Sachs,G;Muallem,S
通讯作者：
Muallem,S