Figure 5.

Optogenetic control of nociceptors in vivo using implantable LED devices. The diagram shows a neuropathic pain patient with the irritable nerve at the site indicated with the large arrow. The implantable LED device is placed along the nerve and the DRG is transduced with a vector to allow for expression of halorhodopsin which causes Cl- influx to the cell in response to light. The combination of the implantable LED and the expressed halorhodopsin allows for termination of the pain signal at the site of the LED through a strong inhibitory current produced by the exogenous channel.