HIPPOCAMPAL TRANSECTION SUPPRESSES SPONTANEOUS AMYGDALAR SEIZURES IN RATS
Abstract number :
2.113
Submission category :
Year :
2003
Submission ID :
3816
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Shin-Ichi Imamura, Shigeya Tanaka, Koichi Akaike, Soichi Obara, Akira Sano, Jun-Ichi Kuratsu Neurosurgery, Kagoshima University, Kagoshima, Kagoshima, Japan; Neurosurgery, Tanaka Neurosurgical Clinic, Kagoshima, Kagoshima, Japan; Neuropsychiatry, Kagoshim
We previously reported that the transection between dorsal and ventral hippocampus attenuated seizures induced by microinjection of kainic acid (KA) into the amygdala (Imamura et. al., 2001). The effect of this procedure on chronic seizure models, however, remains unexamined. This study was designed to assess the effects of hippocampal transection on spontaneous amygdalar seizures in rats.
Experiments were carried out on six male Wistar rats developed with spontaneous amygdalar seizures including spontaneous limbic seizure (SLS) and spontaneous secondarily generalized seizure (SSGS) (Tanaka et. al., 1988). All the animals underwent stereotactic implantation of electrodes in the left amygdala, left dorsal hippocampus, left ventral hippocampus and the left sensorimotor cortex. Evaluation of electrobehavioral changes were evaluated before and after the transection between dorsal and ventral hippocampus using wire knife (Imamura et. al., 2001). Electroencephalograms and behavior were digitally recorded into Hard Disc and analyzed using Macintosh computor (Apple, USA) with PowerLab System (Chart v3.6, ADInstruments, Australia) combined with CCD camera recordings. Recordings were performed during one month each before and after transection and the latency, frequency, and voltage of electroencephalograms were calculated and statically analyzed.
While a total of 18 seizures were captured (SLS: 12, SSGS: 6) before transection, only 8 seizures (SLS: 8, SSGS: 0) were found after transection. It appears that hippocampal transection eliminated SSGS and decreased SLS.
Hippocampal transection attenuated ictal activities of spontaneous amygdalar seizures in rats most likely due to reducing intrahippocampal ictal interaction.
[Supported by: Grant-in-Aid for Priority Areas Research (C) from the Ministry of Education, Sciences, and Culture of Japan ]