In vitro neuronal depolarization and increased synaptic activity induced by infrared neural stimulation

Blake Entwisle; Simon McMullan; Phillip Bokiniec; Simon Gross; Roger Chung; Michael Withford

doi:10.1364/BOE.7.003211

In vitro neuronal depolarization and increased synaptic activity induced by infrared neural stimulation

Biomed Opt Express. 2016 Aug 3;7(9):3211-3219. doi: 10.1364/BOE.7.003211. eCollection 2016 Sep 1.

Authors

Blake Entwisle¹, Simon McMullan², Phillip Bokiniec², Simon Gross¹, Roger Chung², Michael Withford¹

Affiliations

¹ Department of Physics and Astronomy, Faculty of Science and Engineering, Macquarie University, Australia Centre for Ultrahigh bandwidth Devices for Optical Systems, Australia.
² Australian School of Advanced Medicine, Faculty of Human Sciences, Macquarie University, Australia.

Abstract

Neuronal responses to infrared neural stimulation (INS) are explored at the single cell level using patch-clamp electrophysiology. We examined membrane and synaptic responses of solitary tract neurons recorded in acute slices prepared from the Sprague-Dawley rat. Neurons were stimulated using a compact 1890 nm waveguide laser with light delivered to a small target area, comparable to the size of a single cell, via a single-mode fiber. We show that infrared radiation increased spontaneous synaptic event frequency, and evoked steady-state currents and neuronal depolarization. The magnitude of the responses was proportional to laser output.

Keywords: (140.3070) Infrared and far-infrared lasers; (170.0170) Medical optics and biotechnology; (170.1530) Cell analysis; (170.4090) Modulation techniques; (350.5340) Photothermal effects.