Detecting spike propogation with Voltage Sensitive Dyes
Figure 1. Under the guidance of Dejan Zecevic (Dept. Physiology, Yale Medical School) we constructed a microscope that allows for high resolution imaging of GFP containing neurons, patch clamp recording of these neurons, and high resolution, high speed voltage sensitive dye imaging of subcellular compartments of these neurons. The system uses a Yokogawa confocal to image GFP labeled neurons (in order to identify cells that are intact and optimal for the study at hand), a RedShirt imaging camera to record VSD signal at up to 20,000 Hz, a laser to maximally stimulate the VSD near the best wavelength for S/N ratio, and a DIC camera for patching the chosen neuron.
Here we used this system to address the questions - where do action potentials initiate in cerebellar Purkinje cells and do they propagate faithfully?
This study was recently published: Foust, A., Popovic, M., Zecevic, D., McCormick, D.A. (2010) Action potentials initiate in the axon initial segment and propagate through axon collaterals reliably in cerebellar Purkinje neurons. J. Neurosci. 30: 6891-6902.