Opto nongenetics inhibition of neuronal firing

This report highlight the sensitivity of neurons to light in the visible spectrum. A reduction in firing activity upon light stimulation was observed in three of five neuronal types tested from mouse slicesin vitro. Firing reduction was associated with a light ‐induced membrane hyperpolarization and to a modification of action potential shape. The effects of light are likely to be produced by a modest warm up of brain tissue. Implications for optogenetic experiments and possible therapeutic utilization of light stimulation are discussed. AbstractOptogenetics is based on the selective expression of exogenous opsins by neurons allowing experimental control of their electrical activity using visible light. The interpretation of the results of optogenetic experiments is based on the assumption that light stimulation selectively acts on those neurons expressing the exogenous opsins without perturbing the activity of naive ones. Here, we report that light stimulation, of wavelengths and power in the range of those normally used in optogenetic experiments, consistently reduces the firing activity of naive Mitral Cells (MCs) and Tufted Neurons in the olfactory bulb as well as in Medium Spiny Neurons (MSNs) in the striatum. No such effect was observed for cerebellar Purkinje and hippocampal CA1 neurons. The effects on MC firing appear to be mainly due to a light ‐induced increase in tissue temperature, between 0.1 and 0.4°C, associated with the generation of a hyperpolarizing cur...
Source: European Journal of Neuroscience - Category: Neuroscience Authors: Tags: REGISTERED REPORT (STAGE 2) Source Type: research