Recovery of rhythmic activity in a central pattern generator: analysis of the role of neuromodulator and activity-dependent mechanisms.
Recovery of rhythmic activity in a central pattern generator: analysis of the role of neuromodulator and activity-dependent mechanisms.
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DOI：
10.1007/s10827-011-0338-8
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发表时间：
2011-11
影响因子：
1.2
通讯作者：
Golowasch J
中科院分区：
文献类型：
--
作者：
Zhang Y;Golowasch J
甲壳类十足目动物的幽门网络可以经历戏剧性的节律性活动变化。在正常情况下，该网络产生低频节律活动，其强制性地依赖于来自中枢神经系统的神经调节输入的存在。当这种输入被移除（去中心化）时，节奏活动就停止了。在持续缺乏这种输入的情况下，周期性活动在几个小时后以整个网络的情景爆发的形式恢复，随后转变为稳定的节律活动，几乎无法与控制（恢复）区分开来。已经提出，幽门起搏神经元中离子电导水平的活动依赖性改变驱动活动恢复的过程。以前的建模尝试已经捕获了实验观察到的时间变化的某些方面，但关键特征无法重现。在这里，我们研究了一个模型，其中缓慢的活性依赖性调节离子电导和较慢的神经调节剂依赖性调节细胞内Ca2+浓度重现所有的时间特征，这种复苏。这两种调节机制的关键方面是它们的独立性和它们不同的动力学。我们还研究了变异性（噪音）在活动依赖性调节途径中的作用，并观察到它可以帮助减少神经调节剂依赖性途径所需的不切实际的限制。我们的结论是，细胞内Ca2+浓度的小的变化，Ca2+摄取的调节机制，直接针对神经调节剂激活的信号通路，和变化的Ca2+浓度传感信号通路可以解释所观察到的神经元活动的变化。我们的结论都经得起实验分析.
The pyloric network of decapods crustaceans can undergo dramatic rhythmic activity changes. Under normal conditions the network generates low frequency rhythmic activity that depends obligatorily on the presence of neuromodulatory input from the central nervous system. When this input is removed (decentralization) the rhythmic activity ceases. In the continued absence of this input, periodic activity resumes after a few hours in the form of episodic bursting across the entire network that later turns into stable rhythmic activity that is nearly indistinguishable from control (recovery). It has been proposed that an activity-dependent modification of ionic conductance levels in the pyloric pacemaker neuron drives the process of recovery of activity. Previous modeling attempts have captured some aspects of the temporal changes observed experimentally, but key features could not be reproduced. Here we examined a model in which slow activity-dependent regulation of ionic conductances and slower neuromodulator-dependent regulation of intracellular Ca2+ concentration reproduce all the temporal features of this recovery. Key aspects of these two regulatory mechanisms are their independence and their different kinetics. We also examined the role of variability (noise) in the activity-dependent regulation pathway and observe that it can help to reduce unrealistic constraints that were otherwise required on the neuromodulator-dependent pathway. We conclude that small variations in intracellular Ca2+ concentration, a Ca2+ uptake regulation mechanism that is directly targeted by neuromodulator-activated signaling pathways, and variability in the Ca2+ concentration sensing signaling pathway can account for the observed changes in neuronal activity. Our conclusions are all amenable to experimental analysis.
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影响因子：
2.5
作者：
Haedo, Rodolfo J.;Golowasch, Jorge
通讯作者：
Golowasch, Jorge
影响因子：
5.3
作者：
Bucher, D;Prinz, AA;Marder, E
通讯作者：
Marder, E
影响因子：
25
作者：
Aizman, O;Brismar, H;Aperia, A
通讯作者：
Aperia, A
影响因子：
5.3
作者：
Khorkova, Olga;Golowasch, Jorge
通讯作者：
Golowasch, Jorge
影响因子：
5.5
作者：
CATARSI, S;SCURI, R;BRUNELLI, M
通讯作者：
BRUNELLI, M