Effects of Medial Septum Low-frequency Stimulation on Pentylenetetrazol-induced Seizures
Abstract number :
3.426
Submission category :
1. Basic Mechanisms / 1D. Mechanisms of Therapeutic Interventions
Year :
2025
Submission ID :
1418
Source :
www.aesnet.org
Presentation date :
12/8/2025 12:00:00 AM
Published date :
Authors :
Presenting Author: Beatriz Alejandra Garay-Cortes, PhD Student – Instituto de Neurobiologia, UNAM
Victor Magdaleno-Madrigal, PHD – Instituto Nacional de Psiquiatría Ramon de la Fuente
Salvador Almazán- Alvarado, Proffesor – Instituto Nacional de Psiquiatría Ramon de la Fuente
Hiram Luna-Munguia, PhD – Intituto de Neurobiologia, UNAM
Rationale: Deep brain stimulation has become a relevant treatment for patients with poorly controlled epilepsy 1 . However, currently approved protocols only achieve moderate success. Considering the medial septum as a brain structure crucial in modulating the hippocampal theta rhythm in both humans and rodents 2,3 , the aim of this study was to evaluate the anticonvulsant effects of medial septum low-frequency stimulation on pentylenetetrazol-induced seizures.
Methods: 14 male Sprague-Dawley rats (280-300g). In all, tripolar and bipolar electrodes were implanted into the medial septum and dorsal hippocampus, respectively. One week later, all animals were recorded simultaneously in both cerebral regions during 5 minutes. Immediately afterwards, the medial septum 5Hz-stimulation was continuously applied during 30 minutes in 7 rats; the rest of the group received no electrical stimulation. Pentylenetetrazol (PTZ; 50mg/kg, ip) was injected in all animals 15 minutes after electrical stimulation was started. This protocol was repeated for 7 consecutive days.
Results: Animals without septal stimulation had tonic- clonic seizures since the first PTZ administration; two days later, we had a 100% mortality rate. On the other hand, the electrically-stimulated group only showe mioclonic jerks during the whole week; none of the rats died. The power analysis of the 7th day of the stimulated group showed a significant decrease in hippocampal fast-gamma (p<0.01) and high-frequency oscillations (p<0.02). At septum, a significant decrease was observed in delta (p<0.02), alpha (p<0.01), beta (p<0.001), slow-gamma (p<0.03), and fast-gamma oscillations (p<0.01); theta oscillations significantly increased (p<0.05).
Conclusions: The results showed that electrical modulation of the septo-hippocampal pathway prevent the PTZ-induced
generalized seizures. Further studies are required in drug-resistant epilepsy models.
Funding: DGAPA-PAPIIT-UNAM (IN224523-HLM)
Basic Mechanisms