The Effect of Spinal Cord Stimulation on Seizure Susceptibility in Rats

Objectives: Spinal cord stimulation (SCS) activates the thalamus, which may be involved in generation of seizures. SCS may therefore influence seizure susceptibility. We investigated the effect of SCS on seizure susceptibility when performed at low frequency (4 Hz) and a frequency in the typical range of SCS treatment (54 Hz). Materials and Methods: Rats were divided in three groups: control (N = 8), 4 Hz SCS (N = 6), and 54 Hz SCS (N = 8). Tonic-clonic seizures were induced by 10-min intravenous infusion of pentylenetetrazole (PTZ). SCS was started 5 min prior to PTZ infusion and continued for 5 min after infusion offset. Seizure susceptibility was accessed via the latency, number, and total duration of seizures. Results: Four Hz SCS significantly increased seizure susceptibility. Fifty-four Hz SCS produced a nonsignificant trend toward decreased seizure susceptibility. Conclusions: Low-frequency SCS is proconvulsive in rats. Further research needs to investigate if this also applies to humans.