J Korean Epilepsy Soc.  2005 Jun;9(1):17-20.

Properties of Low Magnesium Induced Epileptiform Activity in Rat Visual Cortex Slices

• Choi BJ

Abstract

PURPOSE
The goal of the present study was to investigate the effect of low magnesium on the excitability of visual cortex, observe the induction of epileptiform activity, and define the characteristics of spontaneous activity. METHODS: We divided 19-23 days-old Sprague-Dawley rats into three groups; they were divided by the concentration of Mg, 1 (n=10), 0.5 (n=13), and 0 (n=14) mM. The visual cortex slices from brain were incubated in artificial CSF for one hour, and then extracellular recordings were performed. RESULTS: The latency of interictal epileptiform activity in 0.5 and 0 mM Mg was 26.9+/-11.7 and 13.3+/-2.7 min, the frequency was 1.1+/-0.7 and 5.7+/-0.7 min-1, the amplitude was 1.0+/-0.3 and 1.4+/-0.4 mV, the duration was 15.1+/-15.4 and 587.4+/-398.0 ms. The latency of ictal epileptiform activity in 0 mM Mg was 15.5+/-8.0 min, the frequency was 53.8+/-16.3 /event, the amplitude was 2.9+/-0.7 mV, the duration was 25.2+/-6.0 s. CONCLUSIONS: Low Mg showed the increased excitability in the visual cortex and induced the interictal and ictal spontaneous epileptiform activity. This induction was abolished by D-AP5 and decreased by CNQX. This result may provide insights into the events underlying the epileptogenesis.

Keyword

Magnesium; Experimental epilepsy

MeSH Terms

6-Cyano-7-nitroquinoxaline-2,3-dione
Animals
Brain
Magnesium*
Rats*
Rats, Sprague-Dawley
Visual Cortex*
6-Cyano-7-nitroquinoxaline-2,3-dione
Magnesium