Feb 16, 2026
VTA and PnO Viral Injections With Optrode Implantation
- Cristian González-Cabrera1,
- Matthias Prigge1
- 1Leibniz Institute for Neurobiology, Magdeburg, Germany
Protocol Citation: Cristian González-Cabrera, Matthias Prigge 2026. VTA and PnO Viral Injections With Optrode Implantation. protocols.io https://dx.doi.org/10.17504/protocols.io.n92ld1j2ol5b/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: February 16, 2026
Last Modified: February 16, 2026
Protocol Integer ID: 243383
Keywords: pno viral injections with optrode implantation, pno viral injection, stereotaxic viral injections into vta, optrode implantation, stereotaxic viral injection, optrode headcap, chronic optrode, single skull screw, injection, implantation, vta, pno
Abstract
This protocol describes stereotaxic viral injections into VTA and PnO followed by implantation of a chronic optrode in the same surgical session. The optrode headcap is fixed using RelyX Unicem 2 (3M). A single skull screw is placed for grounding purposes.
Materials
- All materials listed in the injections-only protocol.
- Chronic optrode with integrated optical fiber (e.g., Cambridge Neurotech H8b or H10b, integrated 200 µm fiber, NA 0.39).
- Optional nano-drive (if used).
- RelyX Unicem 2 (3M) for implant fixation.
- One skull screw for electrical ground connection.
- Headstage interface and protective cap.
Troubleshooting
Step-by-Step Procedure
Induce and maintain isoflurane anesthesia (3-4% induction; 1.0-1.5% maintenance) and mount the mouse in the stereotaxic frame on a 37 C heating pad.
Expose and level the skull. Drill craniotomies for VTA and PnO injections and for the optrode implantation site.
Place one skull screw for electrical grounding at a suitable location on the skull, avoiding planned craniotomies.
Inject virus into PnO and VTA as required for the experiment using slow infusion and a brief dwell time before injector withdrawal.
Prepare the optrode for implantation (confirm integrity of the integrated fiber and connector).
Lower the optrode to the planned VTA depth and confirm stable placement.
Fix the optrode (and nano-drive if used) using RelyX Unicem 2 (3M) to build a stable headcap. Allow cement to fully cure before moving the animal.
Administer perioperative analgesia as in the study (carprofen 5 mg kg^-1, subcutaneous).
Close any remaining exposed scalp margins around the headcap as appropriate.
Monitor the animal until fully recovered and perform daily checks during recovery.