Activity Dependent Expression of Na+/K+ Pump Isoforms in Dorsal Root Ganglia Neurons

Na+/K+泵同工型在背根神经节神经元的活性依赖性表达。（PI Dobretsov M.， NSF提案# 9904815）Lay abstract神经元以电信号序列的形式传递信息。信息的模态由神经元连接决定，而信息本身由序列中信号的数量和频率编码。神经元面临的一个问题是，每个信号的传递都伴随着细胞内Na+的积累。如果不从神经元中清除，这些积累的Na+可能会影响整个信号序列和整个信息本身的特性。因此，神经元功能似乎强烈依赖于Na+/K+泵的活性，Na+/K+泵是一种离子转运体，在维持动物细胞内Na+和K+的稳定浓度方面起着重要作用。此外，在不同放电强度和不同细胞内Na+控制需求的神经元中，Na+/K+泵的活性和/或特性可能存在差异。然而，除了理论上的考虑外，关于神经元信号与钠流入神经元、同型表达和神经元Na+/K+泵特性之间的实际关系知之甚少。这些问题将在目前的研究中得到解决，该研究将使用大鼠周围神经元作为神经元模型，并使用电生理、组织学和荧光成像技术作为表征神经元功能和Na+/K+泵表达的工具。

Activity dependent expression of Na+/K+ pump isoforms in dorsal root ganglia neurons. (PI Dobretsov M., NSF proposal # 9904815)Lay AbstractNeurons communicate information as sequences of electrical signals. The modality of the message is determined by the neuronal connections, while the message itself is coded by the number and frequency of signals within the sequence. One of the problems faced by neurons is that the transmission of each signal is followed by an accumulation of Na+ in the cell. If it is not removed from the neuron this accumulated Na+ may affect characteristics of the entire sequence of signals and of the whole message itself. It appears, therefore, that neuronal function should strongly depend on the activity of the Na+/K+ pump, the ion transporter that has a major role in maintaining stable concentrations of Na+ and K+ inside animal cells. Furthermore, it appears that the activity and/or characteristics of the Na+/K+ pump should differ in neurons with different discharge intensity and different needs in intracellular Na+ control. However, aside from theoretical considerations, little is known about actual relationship existing between the neuron signaling and sodium influx into the neuron, isoform expression, and characteristics of the neuronal Na+/K+ pump. These questions will be addressed in the present investigation that will use the rat peripheral neurons as a neuronal model, and electrophysiological, histological, and fluorescent imaging techniques as tools to characterize neuronal function and expression of the Na+/K+ pump.