LIGNOCAINE-INDUCED CONVULSION DOES NOT INDUCE C-FOS PROTEIN (C-FOS) IN RAT HIPPOCAMPUS

Recent studies have shown that proto-oncogene c-fos mRNA is induced in the central nervous system by a variety of stimuli including generali sed convulsions. In this study, the expression of c-fos protein (c-Fos ) following lignocaine-induced convulsions was examined and Compared w ith that following convulsions induced by non-anesthetic convulsants, such as pentylenetetrazol, kainic acid and electroconvulsive shocks, i n rat brain. Administration of 120 mg.kg(-1) lignocaine by the intrape ritoneal route induced generalised convulsions in all rats examined wi thin 10 min. C-Fos was markedly induced in the piriform cortex and amy gdala, and slightly induced in the neocortex and thalamus, while no c- Fos expression was observed in the hippocampus. In contrast, c-Fos exp ression following generalised convulsions induced by non-anaesthetic c onvulsants was very marked in the hippocampal region, piriform cortex and amygdala, and extended to the thalamus and neocortex. These result s contradict these of previously reported local cerebral metabolic stu dies using 2-deoxyglucose as a metabolic marker, and suggest that lign ocaine-induced convulsions, unlike those induced by nonanaesthetic con vulsants, may not cause severe sequelae (plastic changes) in the hippo campus.