Autoradiographic analysis of [35S]TBPS binding in entorhinal cortex-kindled rat brains.
A quantitative autoradiographic analysis of [35S]t-butylbicyclophosphorothionate (TBPS) binding to the gamma-aminobutyric acid (GABA)-mediated chloride ionophore was carried out in 104 brain areas of entorhinal cortex-kindled and control rats. Subjects were sacrificed either 24 h or 28 days after the last kindled seizure. Kindled subjects in the 24 h group showed reductions in mean [35S]TBPS binding in the lateral nucleus of the amygdala (-31%), the infralimbic cortex (-14%), and the paracentral nucleus of the thalamus (-22%). At 28 days, reductions in binding were observed in the infralimbic cortex (-15%) and the paracentral nucleus of the thalamus (-18%). These data suggest that repeated seizures (kindling) modify the GABA-mediated chloride ionophore, and that in some brain areas related to seizure generalization the modifications are very long lasting.
Petrasek
J S
JS
Department of Pharmacology, University of Toronto, Ont., Canada.
Nobrega
J N
JN
Kish
S J
SJ
Burnham
W M
WM
D000818:Animals; D001345:Autoradiography; D001643:Bridged Bicyclo Compounds / Q000378:metabolism*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002138:Calibration; D003292:Convulsants / Q000378:metabolism*; D003720:Densitometry; D006624:Hippocampus / Q000378:metabolism*; D007696:Kindling, Neurologic / Q000378:metabolism*; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D011963:Receptors, GABA-A / Q000378:metabolism*
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003292:Convulsants; D011963:Receptors, GABA-A; C037476:tert-butylbicyclophosphorothionate