We discuss two experimental methods to reveal ChR2 current during an action potential: an “optical AP clamp” and its approximation employing measured current-voltage curve for ChR2. The methods are applicable to voltage- and light-sensitive ion currents operating in excitable cells, e.g. cardiomyocytes or neurons.

Optical spindle-rhythm stimulation prolonged the increase in 12-30Hz activity in ChR2-VGAT mice only (p=0.023). Spindle-rhythm stimulation also increased the incidence and duration of sleep spindle-like oscillations in ChR2-VGAT mice only (all p≤0.001).

Oct 16, 2021 · Channelrhodopsin (ChR2) and Halorhodopsin (NpHR) are light-sensitive proteins commonly used in optogenetic stimulation, which can regulate neuron activities with millisecond precision through light stimulation (Parker et al. 2016).

ChR2 photostimulation in vivo reliably generated stimulus-locked action potentials10–13at frequencies up to 50 Hz. Here we show that naive mice readily learned to detect brief trains of action...

ChR2 (T159C), which we refer to as “ChR2-TC” or simply “TC,” generates very large photocurrents and sensitizes neurons to very low light intensities. The E123T/T159C double mutant (ET/TC) enables reliable and sustained optical stimulation of hippocampal pyramidal neurons up to 60 Hz.

Sep 26, 2023 · Importantly, we showed that blue light (465nm) selectively activated somatic BLA ChR2 (Figure 1N), while red light (615nm) activated Chrimson at vHPC terminals to induce optically-evoked EPSCs (oEPSCs). Neurons were held at −70mV; ChR2 was pulsed for 30Hz, at 20s to mimic our in vivo BLA stimulation paradigm . A baseline of 10 oEPSC (615nm ...

Sep 21, 2006 · Here we will focus on physiological issues governing one such new approach—application of an algal light-gated ion channel Channelrhodopsin-2 for photostimulation 5, 6, 7, 8 —and compare the...

Feb 13, 2025 · To investigate the ion permeation mechanism of ChR2 at a molecular level, we performed molecular dynamics (MD) simulations using wild-type ChR2 with all-trans-retinal (ChR2-trans) and 13-cis-retinal (ChR2-cis) and L132C mutant of ChR2 with 13-cis-retinal (CatCh) systems and compared each trajectory.

Feb 22, 2017 · Two-photon images of large populations of individual L2/3 neurons (461 ± 164, mean ± SD) were acquired at ≈30Hz and simultaneously streamed to a dedicated computer for real-time processing (Figure 1 D).

The light-gated cation channel Channelrhodopsin-2 (ChR2) is a powerful and versatile tool for controlling neuronal activity. Currently available versions of ChR2 either distribute uniformly throughout the plasma membrane or are localised ...