Autoradiographic analysis of [35S]t-butylbicyclophosphorothionate binding in kindled rat hippocampus shows different changes in CA1 area and fascia dentata.
We studied the binding of [35S]t-butylbicyclophosphorothionate to the GABAA receptor-mediated chloride channel in the CA1 area and fascia dentata of control and Schaffer collateral kindled rats, by means of semi-quantitative autoradiography. The [35S]t-butylbicyclophosphorothionate binding was determined at three stages during kindling acquisition: (i) after six afterdischarges, (ii) after 14 afterdischarges and (iii) after the induction of fully kindled seizures. Furthermore, the binding was studied at the long-term stage, 28 days after the last generalized tonic-clonic seizure [Racine R. J. (1972) Electroenceph. clin. Neurophysiol. 32, 281-294]. The binding was investigated at three [35S]t-butylbicyclophosphorothionate concentrations, 4, 47.5 (KD value) and 180 nM (Bmax value). A significant decrease in [35S]t-butylbicyclophosphorothionate binding in the CA1 area (-6 to -20%) and hilar formation (-17 to -37%), in one or more of the three [35S]t-butylbicyclophosphorothionate concentrations tested at the six and 14 afterdischarges and fully kindled stages was observed, but no significant changes at the long-term kindling stage were found. In contrast, the granular and molecular layers of the fascia dentata presented a significant increase in [35S]t-butylbicyclophosphorothionate binding (+15 to +38%) at the 14 afterdischarges, fully kindled and long-term kindled stages.(ABSTRACT TRUNCATED AT 250 WORDS)
Titulaer
M N
MN
Graduate School for the Neurosciences, Institute of Neurobiology, Faculty of Biology, University of Amsterdam, The Netherlands.
Kamphuis
W
W
Lopes da Silva
F H
FH
D000818:Animals; D001345:Autoradiography / Q000379:methods; D001643:Bridged Bicyclo Compounds / Q000378:metabolism*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D018118:Chloride Channels / Q000032:analysis / Q000378:metabolism*; D003292:Convulsants / Q000378:metabolism; D004558:Electric Stimulation; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D007696:Kindling, Neurologic; D007700:Kinetics; D008297:Male; D009474:Neurons / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D009928:Organ Specificity; D017966:Pyramidal Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000032:analysis / Q000378:metabolism*; D013462:Sulfur Radioisotopes
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D018118:Chloride Channels; D003292:Convulsants; D011963:Receptors, GABA-A; D013462:Sulfur Radioisotopes; C037476:tert-butylbicyclophosphorothionate