Benquet Pascal, Pichon Yves, Tiaho François
UMR 6026, Campus de Beaulieu, Bt 13, Université de Rennes 1, 35042 Rennes Cedex, France.
Neurosci Lett. 2004 Jul 29;365(3):228-32. doi: 10.1016/j.neulet.2004.05.002.
Voltage-gated calcium currents are important for the survival and growth of embryonic cockroach brain neurons in primary culture. In the present experiments, we have studied, using the patch-clamp technique, the evolution with time in culture of the voltage-dependency and of the pharmacological properties of the calcium conductance of these neurons during the formation of a network. We have observed a progressive increase of the high-voltage-activated calcium conductance and a 10mV shift of the voltage-dependency of activation towards more negative potentials. The proportion of the R-like calcium current component increased during network formation. At the same time, the highly omega-AgaTxIVA-sensitive P-like component of the current is progressively replaced by a component which is less sensitive to the toxin. The origin and functional implications of these modifications are discussed.
电压门控钙电流对于原代培养的胚胎蟑螂脑神经元的存活和生长至关重要。在本实验中，我们使用膜片钳技术研究了这些神经元在网络形成过程中钙电导的电压依赖性和药理学特性随培养时间的演变。我们观察到高压激活钙电导逐渐增加，激活的电压依赖性向更负电位偏移10mV。在网络形成过程中，R样钙电流成分的比例增加。同时，电流中对ω-AgaTxIVA高度敏感的P样成分逐渐被对该毒素不太敏感的成分所取代。讨论了这些修饰的起源和功能意义。
