In-depth activation of channelrhodopsin 2-sensitized excitable cells with high spatial resolution using two-photon excitation with a near-infrared laser microbeam.

ABSTRACT: We used two-photon excitation with a near-infrared (NIR) laser microbeam to investigate activation of channelrhodopsin 2 (ChR2) in excitable cells for the first time to our knowledge. By measuring the fluorescence intensity of the calcium (Ca) indicator dye, Ca orange, at different wavelengths as a function of power of the two-photon excitation microbeam, we determined the activation potential of the NIR microbeam as a function of wavelength. The two-photon activation spectrum is found to match measurements carried out with single-photon activation. However, two-photon activation is found to increase in a nonlinear manner with the power density of the two-photon laser microbeam. This approach allowed us to activate different regions of ChR2-sensitized excitable cells with high spatial reso

SUBMITTER: Mohanty SK 

PROVIDER: S-EPMC2553121 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature