Temporal pattern of AP-1 DNA-binding activity in the rat hippocampus following a kindled seizure.
DNA binding by transcripton factor AP-1 was enhanced remarkably following kindling stimulation in rat amygdala. Maximum increase occurred 2 h after stimulation with return to baseline within 24 h. Supershift and western analyses revealed that 38,000 mol. wt Fos-related antigen and JunD were the main components of the evoked AP-1 complexes at the time their induction reached maximum. AP-1 induction 2 h after the last kindling stimulation was more prominent in samples from previously kindled rats than in those from non-kindled rats. This study sought to establish the role of AP-1 in plastic changes of the hippocampus associated with kindling. Male Sprague-Dawley rats were kindled from the left amygdala until they exhibited Racine15 class 5 generalized seizures. Nuclear proteins were extracted from dorsal hippocampi obtained from 0 to 24 h after final stimulations. From these, we evaluated the temporal pattern of DNA binding by AP-1 using a gel mobility-shift assay with a 32P-labelled AP-1 probe. Supershift and western analyses were added to investigate components of the seizure-evoked AP-1 complexes. Our results suggest that the basal level of AP-1 complexes is not associated with the seizure susceptibility in kindling. However, development of kindling appears to facilitate stimulus-evoked AP-1 induction, probably via plastic changes in the central nervous system. AP-1 may mediate such changes by regulating expression of certain genes.
Kashihara
K
K
Department of Neurology, Okayama University Medical School, Japan.
Sato
K
K
Akiyama
K
K
Okada
S
S
Ishihara
T
T
Hayabara
T
T
Shomori
T
T
D000704:Analysis of Variance; D000818:Animals; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D016384:Consensus Sequence; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D006624:Hippocampus / Q000378:metabolism* / Q000502:physiology / Q000503:physiopathology; D007696:Kindling, Neurologic / Q000502:physiology*; D007700:Kinetics; D008297:Male; D009687:Nuclear Proteins / Q000096:biosynthesis; D015345:Oligonucleotide Probes; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012640:Seizures / Q000378:metabolism* / Q000503:physiopathology; D013997:Time Factors; D018808:Transcription Factor AP-1 / Q000096:biosynthesis*; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D015345:Oligonucleotide Probes; D018808:Transcription Factor AP-1