Epileptiform activity of the anterior dorsal hippocampal network induced by acute tetanization of the right posterior dorsal hippocampus of the rat.
- Author:
Wen-Ting WANG
1
;
Dan HAN
;
Zu-Yu ZOU
;
Jun ZENG
Author Information
1. Department of Physiology, Medical College, Wuhan University, Wuhan 430071.
- Publication Type:Journal Article
- MeSH:
Animals;
Electric Stimulation;
Epilepsy, Temporal Lobe;
physiopathology;
Evoked Potentials;
Hippocampus;
physiopathology;
Male;
Nerve Net;
physiopathology;
Neurons;
physiology;
Rats;
Rats, Sprague-Dawley
- From:
Acta Physiologica Sinica
2003;55(3):339-348
- CountryChina
- Language:Chinese
-
Abstract:
The purpose of the present work was to study the role of unilateral hippocampal neural network in hippocampal epileptogenesis and its cellular mechanisms. Experiments were performed on 45 Sprague-Dawley adult rats. Acute tetanization (60 Hz, 2 s, 0.4 - 0.6 mA) of the right posterior dorsal hippocampus (ATPDH) was used to induce hippocampal epilepsy. The single unit discharges and the depth electrographs were synchronously recorded with a glass microelectrode and a pair of stainless concentric electrodes in the ipsilateral anterior dorsal hippocampus (HPC). The results demonstrated that: (1) some primary unit after-discharges were synchronized with electrographic after-discharges in the anterior dorsal HPC network after eight or nine tetanic trains were administered. Others desynchronized with 5 - 90 Hz primary depth electrographic after-discharges; (2) primary electrographic after-discharges were driven by primary unit after-discharges in the anterior dorsal HPC; (3) primary unit after-discharges were induced by brief primary electrographic after-discharges; and (4) plasticity of primary electrographic after-discharges and inhibition of single neuron firing were induced by repetitive ATPDH. The results suggest that hippocampal pathophysiologic network along the temporal-septal axis of the HPC is re-established by the repetitive ATPDH. There are plastic interactions between single neurons and its network during this re-establishment, which may be involved in the generation of "seizure oscillation". Over-activation of an intrinsic inhibition of the HPC along its temporal-septal axis might be involved in hippocampal network epileptogenesis.
