Cortical kindling induces elevated levels of AMPA and GABA receptor subunit mRNA within the amygdala/piriform region and is associated with behavioral changes in the rat.
Cortical kindling causes alterations within the motor cortex and results in long-standing motor deficits. Less attention has been directed to other regions that also participate in the epileptiform activity. We examined if cortical kindling could induce changes in excitatory and inhibitory receptor subunit mRNA in the amygdala/piriform regions and if such changes are associated with behavioral deficits. After cortical kindling, amygdala/piriform regions were dissected to analyze mRNA levels of NMDA, AMPA, and GABA receptor subunits using reverse transcription polymerase chain reaction, or rats were subjected to a series of behavioral tests. Kindled rats had significantly greater amounts of GluR1 and GluR2 AMPA receptor mRNA, and alpha1 and alpha2 GABA receptor subunit mRNA, compared with sham controls, which was associated with greater anxiety-like behaviors in the elevated plus maze and reduced freezing behaviors in the fear conditioning task. In summary, cortical kindling produces dynamic receptor subunit changes in regions in addition to the seizure focus.
Henderson
Amy K
AK
Department of Psychology, University of Calgary, Calgary, AB, Canada. ahender@ucalgary.ca
Galic
Michael A
MA
Teskey
G Campbell
GC
D000679:Amygdala / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology; D004558:Electric Stimulation / Q000379:methods; D005106:Exploratory Behavior / Q000502:physiology; D007696:Kindling, Neurologic / Q000235:genetics / Q000378:metabolism*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D020318:Rats, Long-Evans; D018091:Receptors, AMPA / Q000235:genetics* / Q000378:metabolism; D018079:Receptors, GABA / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D018091:Receptors, AMPA; D018079:Receptors, GABA; C104722:glutamate receptor ionotropic, AMPA 2