title: Behavioral and EEG effects of GABAergic manipulation of the nigrotectal pathway in the Wistar audiogenic rat strain.
abstract: The superior colliculus (SC), substantia nigra pars reticulata (SNPr), and striatum have been characterized as important structures involved in the modulation of seizure activity. In the current study, bicuculline (GABA(A) antagonist) and muscimol (GABA(A) agonist) were microinjected into the deep layers of either the anterior SC (aSC) or posterior SC (pSC) of genetically developed Wistar audiogenic rats. Behavior and EEG activity were studied simultaneously. Only muscimol microinjected into the pSC had behavioral and EEG anticonvulsant effects in Wistar audiogenic rats, eliciting EEG oscillation changes in both SNPr and pSC, primarily during tonic seizures. The SC of Wistar audiogenic rats thus comprises two functionally different subregions, pSC and aSC, defined by distinct behavioral and EEG features. The pSC has proconvulsant audiogenic seizure activity in Wistar audiogenic rats. Our data suggest that this phenomenon may be a consequence of the genetic selection of the Wistar audiogenic rat strain.
authors.affiliation: Neuroscience and Behavioral Sciences Department, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Franco
authors.initials: F
authors.lastname: Rossetti
authors.forename: Marcelo Cairrão Araujo
authors.initials: MC
authors.lastname: Rodrigues
authors.forename: José Antônio Cortes
authors.initials: JA
authors.lastname: de Oliveira
authors.forename: Norberto
authors.initials: N
authors.lastname: Garcia-Cairasco
mesh_terms: D000161:Acoustic Stimulation / Q000009:adverse effects; D000704:Analysis of Variance; D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D003342:Corpus Striatum / Q000502:physiology*; D004569:Electroencephalography; D058785:GABA-A Receptor Agonists / Q000494:pharmacology; D058787:GABA-A Receptor Antagonists / Q000494:pharmacology; D007696:Kindling, Neurologic; D008297:Male; D009118:Muscimol / Q000494:pharmacology; D009434:Neural Pathways / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000209:etiology* / Q000473:pathology*; D013378:Substantia Nigra / Q000502:physiology*; D013477:Superior Colliculi / Q000187:drug effects; D014741:Video Recording; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D058785:GABA-A Receptor Agonists; D058787:GABA-A Receptor Antagonists; D009118:Muscimol; D005680:gamma-Aminobutyric Acid; D001640:Bicuculline