Apr 28, 2026

PTZ Seizure Challenge: Assessment of Seizure Sensitivity in Mice

DOI
https://dx.doi.org/10.17504/protocols.io.q26g7ok6qvwz/v1
  • 1KU Leuven;
  • 2Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815
Sarah van Veen
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DOI: https://dx.doi.org/10.17504/protocols.io.q26g7ok6qvwz/v1
Protocol Citation: Sarah van Veen, Zsuzsanna Callaerts-Végh 2026. PTZ Seizure Challenge: Assessment of Seizure Sensitivity in Mice. protocols.io https://dx.doi.org/10.17504/protocols.io.q26g7ok6qvwz/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: April 21, 2026
Last Modified: April 28, 2026
Protocol  Integer ID: 315431
Keywords: ASAPCRN, ptz seizure challenge, seizure sensitivity, assessment of seizure sensitivity, ptz, injection of pentylenetetrazol, onset of seizure, seizure, pentylenetetrazol, mice this protocol, adult mice, mice
Funders Acknowledgements:
Aligning Science Across Parkinson's
Grant ID: ASAP-000458
Fonds Wetenschappelijk Onderzoek (FWO)
Grant ID: G011424N
Abstract
This protocol describes the assessment of seizure sensitivity in adult mice using an acute intraperitoneal
(i.p.) injection of pentylenetetrazol (PTZ) dissolved in saline (2.5 mg/mL), injected at 1% body weight.
Behavior is video-recorded for 15 min in a small observation box and analyzed with EthoVision XT (Noldus
Information Technology). Occurrence and onset of seizure-related behaviors are scored manually.
Guidelines
•       PTZ solutions should be prepared fresh; do not freeze and reuse.
•       Testing order should be randomized; blind experimenter to genotype where possible.
•       Clean observation box with 70% ethanol between animals, allow to dry before placing next mouse
Materials
AB
SubjectsAdult WT and KO littermates (~2 months old)
DrugPentylenetetrazol (PTZ), 2.5 mg/mL in sterile saline (0.9% NaCl), injected at 1% body weight (i.e. 25 mg/kg)
VehicleSterile saline (0.9% NaCl)
Observation chamberSmall box, 15 x 15 cm floor area, 30 cm high
RecordingVideo camera positioned in front of observation box
Tracking softwareEthoVision XT (Noldus Information Technology)
Session duration15 min post-injection
Safety warnings
PTZ is a convulsant agent. Handle with gloves and follow institutional biosafety procedures. Animals experiencing severe tonic-clonic seizures should be monitored and removed if humane endpoints are reached, per local IACUC/ethics committee guidelines.
Ethics statement
Experiments involving animals must be conducted according to internationally-accepted standards and should always have prior approval from an Institutional Animal Care and Use Committee (IACUC) or equivalent ethics committee(s).
Before start
• Prepare PTZ solution fresh on the day of testing: dissolve in sterile saline to 2.5 mg/mL. Injection
volume is 1% body weight (10 mL/kg), giving a dose of 25 mg/kg.
• Set up EthoVision XT: define arena boundaries for the 15 x 15 cm observation box, confirm camera
positioning.
• Ensure observation box is clean and odor-free.
• Allow mice to acclimate to the procedure room for 30 min before injection.
 
Prepare injection
Calculate PTZ volume per animal body weight (concentration: 2.5 mg/mL; injection volume: 1%
body weight, i.e., 10 mL/kg; dose: 25 mg/kg). Draw up PTZ solution in a 1 mL syringe with a 27G
needle.
Administer PTZ
Restrain mouse and administer PTZ i.p. at 1% body weight (25 mg/kg). Note exact injection time.
Place in observation box
Immediately after injection, place the mouse in the observation box (15 x 15 cm, 30 cm high). Begin
video recording and EthoVision XT tracking simultaneously.
Record and score behavior for 15 min
Record behavior continuously for 15 min. Score the occurrence and onset time of the following
seizure-related behaviors: (1) supine position (laying flat on floor), (2) head jerks, (3) Straub tail, (4)
clonic seizures, (5) tonic seizures.
Monitor and ensure humane endpoint
Observe animals throughout. If an animal reaches a humane endpoint (sustained generalized
convulsions >60 s), intervene per institutional ethics protocol and record endpoint time. Behavioral
scoring should be performed blind to genotype.
Data analysis
For each animal, record the occurrence and latency to onset of each scored behavior: supine
position, head jerks, Straub tail, clonic seizures, and tonic seizures. Compare occurrence and
latency between WT and KO using appropriate non-parametric statistics (e.g., Mann-Whitney U) or
survival analysis for latency to seizure onset.
Expected result
PTZ injection induces a range of seizure-related behaviors. Increased severity, higher occurrence, or shorter latencies to seizure behaviors in KO animals compared to WT indicate heightened seizure susceptibility.