Measurement of extracellular potassium dynamics

我的研究项目是调查环境压力对神经回路的影响，这些神经回路控制着诸如通风和逃生等关键行为。我对一些动物如何更好地应对压力的机制很感兴趣。例如，暴露在压力环境中的动物随后会对未来的压力产生耐受性。这项研究与加拿大人有关，因为它强调了全球变暖可能对昆虫产生的行为后果。例如，对高温耐受性增强的草原蚱蜢可能会进一步扩散，对作物产生更大的影响。为了在高温下控制这些行为，神经元必须调节神经元内外特定离子的离子浓度。在高温下，这些梯度就会消失。先前受到压力的动物在随后的压力暴露中能够更好地维持这些离子梯度。尽管许多离子对正常的神经功能至关重要，但钾离子尤其令人感兴趣。钾离子通常存在于神经元内部，但当温度超过细胞维持这种梯度的能力时，就会出现大量的钾离子释放，使人虚弱。当这种情况发生时，神经元和它们控制的行为停止运作。我们感兴趣的是是什么调节了钾的释放。要做到这一点，我们必须使用测量细胞内外离子浓度的设备。我正在申请资金购买设备，使我的学生和我能够测量细胞外钾的动态与控制蝗虫通风的神经回路的适当功能有关。

My research program investigates the effects of environmental stress on neural circuits that control crucial behaviours such as ventilation and escape. I am interested in the mechanisms that underlie how some animals are better able to handle stress. For instance, animals which have been exposed to a stressful situation subsequently develop tolerance to future stresses. This research is relevant to Canadians because it highlights the behavioural consequences that global warming may have on insects. For example prairie grasshoppers with increased tolerance to high temperatures may spread further and have a greater impact on crops. In order to control these behaviours at high temperatures, neurons must regulate the ionic concentrations of specific ions inside and outside the neurons. At high temperatures these gradients break down. Animals that have received a prior exposure to stress are better able to maintain these ionic gradients during subsequent exposures to stress. Although many ions are crucial for proper neural function, potassium is of particular interest. Potassium ions usually reside inside the neuron, but at a critical point when the temperature exceeds the ability of the cell to maintain this gradient a massive and debilitating release of potassium ensues. When this happens neurons and the behaviours they control cease to function. We are interested in what regulates this release of potassium. To accomplish this we must use equipment that measures ionic concentrations inside and outside the cell. I am requesting funding to purchase equipment that will enable my students and me to measure the dynamics of extracellular potassium in relation to appropriate function of the neural circuit that controls ventilation in locusts.