Journal: Physiological Reports

Article Title: Validation of optical voltage reporting by the genetically encoded voltage indicator VSFP-Butterfly from cortical layer 2/3 pyramidal neurons in mouse brain slices

doi: 10.14814/phy2.12468

Figure Lengend Snippet: Butterfly VSFP 2.1 robustly monitors voltage transients from populations of L2/3 pyramidal neurons in response to electrical stimulation. (A) Widefield images of Butterfly expression, mCitrine, yellow and mKate2, red, in a living slice (spatial scale bar 100 μ m) with position of electrical stimulation and recording electrodes; inset shows a schematic of Butterfly FRET pairs. (B) Widefield imaging responses from Butterfly mCitrine (donor) and mKate2 (acceptor) (average of 10 sweeps, scale bars 1 sec; 0.1% Δ F / F 0 and Δ R / R 0 apply to both 1× and 5× responses), from a region of interest placed in L2/3 (rectangle in A), in response to 1× and 5× electrical stimulation (20 V, downward arrows) with accompanying LFPs, scale bars 0.1 mV; 50 ms. Note the decrease in donor fluorescence and increase in acceptor fluorescence as expected from modulation of FRET efficacy. (C) Summary data from seven animals illustrating the robust and reproducible nature of the optical readout, all individual values are shown with mean ± SEM in gray. (D) Butterfly signal as a function of stimulation intensity, values are mean ± SEM (data is from 5 to 8 slices at each stimulation intensity). Inset is an example recording, note the fast (arrowhead) and slow components of the Butterfly signal at high stimulation intensities, scale bars 100 ms; 0.2% Δ R / R 0 . (E) Imaging of electrical stimulation-induced voltage transients using two-photon microscopy mCitrine (left, yellow) and mKate2 fluorescence (right, red); stimulating (center) and recording electrode (top right corner), scale bar 100 μ m. Lower panel shows color-coded sequence of voltage maps 40 ms before to 160 ms after stimulation ( t = 0, 5 pulses, 0.2 ms, 100 Hz). Depolarization initiates close to the stimulating electrode tip and then spreads to nearby areas. (F) Donor (mCitrine), Acceptor (mKate2), and Ratio (mKate2/mCitrine) fluorescence transients from the region of interest above (scale bars 1% Δ F / F 0 and Δ R / R 0 ; 250 ms). Black arrows indicate time of electrical stimulation. Traces represent average over 25 trials. Inset shows associated LFP, scale bars 1 mV; 10 ms.

Article Snippet: Single, 1× and repeat, 5× (50 Hz) electrical stimulation (constant positive polarity voltage, 100–200 μ sec duration, Digitimer DS2A, Iso-Flex AMPI, Israel) used a monopolar-stimulating electrode (1–1.5 MΩ, resistance) placed remotely (4–500 μ m away but in the cortical column, or closer in L2/3 for 2-photon [2P] imaging) from the recording electrode and imaging area.

Techniques: Expressing, Imaging, Fluorescence, Microscopy, Sequencing

Journal: Physiological Reports

Article Title: Validation of optical voltage reporting by the genetically encoded voltage indicator VSFP-Butterfly from cortical layer 2/3 pyramidal neurons in mouse brain slices

doi: 10.14814/phy2.12468

Figure Lengend Snippet: Electrical stimulation-induced Butterfly VSFP2.1 signals from the layer 2/3 population are predominantly synaptic but also contain a fast action potential-mediated component.(A) High stimulation voltage (90 V) -induced Butterfly response integrated over a large region of L2/3 (16× objective, 300 μ m × 300 μ m, average of five sweeps, widefield imaging) showing an initial fast component followed by a slower, longer lasting component (scale bars 0.5% Δ R / R 0 , 500 ms). The LFP exhibits a fast antidromic action potential and slower synaptic response (scale bars 0.1 mV, 5 ms), stimulus artifacts are removed. (B) pharmacological treatment with the excitatory glutamatergic synaptic blockers CNQX and APV reduces the Butterfly signal, leaving a TTX sensitive component remaining. Error bars are mean ± SEM and *** and * represent P < 0.001 and P < 0.05 (one-way ANOVA).

Article Snippet: Single, 1× and repeat, 5× (50 Hz) electrical stimulation (constant positive polarity voltage, 100–200 μ sec duration, Digitimer DS2A, Iso-Flex AMPI, Israel) used a monopolar-stimulating electrode (1–1.5 MΩ, resistance) placed remotely (4–500 μ m away but in the cortical column, or closer in L2/3 for 2-photon [2P] imaging) from the recording electrode and imaging area.

Techniques: Imaging

Journal: Cell reports

Article Title: Pathway-specific alterations in striatal excitability and cholinergic modulation in a SAPAP3 mouse model of compulsive motor behavior

doi: 10.1016/j.celrep.2023.113384

Figure Lengend Snippet:

Article Snippet: ISO-Flex stimulus isolator , Microprobes for Life Sciences , RRID: SCR_018945.

Techniques: Virus, Recombinant, Software, Laser-Scanning Microscopy, Microscopy, Ointment