What Is the Role of GABA-B System in Cortical Epileptic Afterdischarges?
Abstract number :
2.027
Submission category :
Year :
2001
Submission ID :
2327
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
P. Mare[shacek], Institute of Physiology, Academy of Sciences, Prague, Czech Republic; J. Lindovsk[yacute], Institute of Physiology, Academy of Sciences, Prague, Czech Republic; R. Haugvicov[aacute], Institute of Physiology, Academy of Sciences, Prague, C
RATIONALE: To examine the role of GABA-B system in generation of cortical epileptic afterdischarges (ADs) and postictal depression.
METHODS: ADs were elicited by low-frequency electrical stimulation of sensorimotor cortex in rats with implanted electrodes. Threshold currents were estimated with stimulations repeated in 10-min intervals with increasing intensities, baclofen (Bc) was injected 10 min before the start of experiment. An anticonvulsant effect was measured in a series of 4 stimulations of the same intensity. Postictal depression was studied by means of paired stimulations with different interstimulation intervals. Bc was always injected in a dose of 6 mg/kg i.p., control animals received the same volume of saline.
RESULTS: Bc did not change threshold for elicitation of the spike-and-wave type of AD. Using repeated stimulations Bc exhibited only moderate anticonvulsant effect. Postictal depression was augmented when 2-min interval was used. No postictal depression was found with longer interstimulation intervals.
CONCLUSIONS: Bc did not markedly influence generation of the cortical epileptic ADs but was able to potentiate postictal depression, i.e. GABA-B system may play a role in an arrest of these ADs.
Support: Supported by a grant No.309/99/0207 of the Grant Agency of the Czech Republic.