Dec 22, 2025
STN optotagging
- Asa Mackenzie1
- 1Lund University
Protocol Citation: Asa Mackenzie 2025. STN optotagging. protocols.io https://dx.doi.org/10.17504/protocols.io.rm7vzen3rvx1/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: December 22, 2025
Last Modified: April 20, 2026
Protocol Integer ID: 235674
Keywords: ASAPCRN, optotagging stn
Funders Acknowledgements:
Aligning Science Across Parkinson's
Grant ID: ASAP-020600
Abstract
STN optotagging
STN optotagging
A custom-made optrode was made with an optic fiber (100 mm diameter, Thorlabs) connected to a laser (MBL-III-473 nm-100 mW laser, CNI Lasers, Changchun, China) mounted and glued on the recording glass micropipette which was filled with 2% pontamine sky blue in 0.5 mM sodium acetate (tip diameter 1–2 mm, resistance 10–15 MU).
The distance between the end of the optic fiber and
the tip of the recording pipette varied between 650 nm and 950 nm.
Extracellular action potentials were recorded and amplified with
an Axoclamp-2B and filtered (300 Hz/0.5 kHz).
Single extracellular spikes were collected online (CED 1401, SPIKE2; Cambridge Electronic Design).
The laser power was measured before starting each experiment using a power meter (PM100D; Thorlabs). The baseline was recorded for 100 s for each neuron before starting any light stimulation protocols which were set and triggered with Spike2 software.
Light protocol consisted in a peristimulus time histogram (PSTH, 0.5 Hz, 5 ms pulse duration, 5–8 mW) for at least 100 s followed, after returned to baseline, by a ‘‘behavioral’’ protocol corresponding to the parameters used for behavioral experiments (20 Hz, 5 ms pulse duration, 5–8 mW).