Amygdala kindling potentiates seizure-stimulated immediate-early gene expression in rat cerebral cortex.
Kindling induces long-term adaptations in neuronal function that lead to a decreased threshold for induction of seizures. In the present study, the influence of amygdala kindling on levels of mRNA for the immediate-early genes (IEGs) c-fos, c-jun, and NGF1-A were examined both before and after an acute electroconvulsive seizure (ECS). Although amygdala kindling did not significantly influence resting levels of c-fos mRNA in cerebral cortex, ECS-stimulated levels of c-fos mRNA (examined 45 min after ECS) were approximately twofold greater in the cerebral cortex of kindled rats relative to sham-treated controls. The influence of kindling on IEG expression was dependent on the time course of kindling, as ECS-stimulated levels of c-fos mRNA were not significantly increased in stage 2 kindled animals. ECS-stimulated levels of c-jun and NGF1-A mRNA were also significantly increased in cerebral cortex of kindled rats relative to sham-treated controls. The influence of kindling on IEG expression was long-lasting because an acute ECS stimulus significantly elevated levels of c-fos and c-jun mRNA in the cerebral cortex of animals that were kindled 5 months previously. In contrast to these effects in cerebral cortex, kindling did not influence ECS-stimulated levels of c-fos mRNA in hippocampus. Finally, immunohistochemical studies revealed lamina-specific changes in the cerebral cortex.(ABSTRACT TRUNCATED AT 250 WORDS)
Duman
R S
RS
Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut.
Craig
J S
JS
Winston
S M
SM
Deutch
A Y
AY
Hernandez
T D
TD
D000679:Amygdala / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism / Q000502:physiology*; D005786:Gene Expression Regulation; D016762:Genes, fos; D007696:Kindling, Neurologic / Q000235:genetics*; D008297:Male; D009414:Nerve Growth Factors / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000235:genetics*
D009414:Nerve Growth Factors; D012333:RNA, Messenger