Autoradiographic analysis of [35S]t-butylbicyclophosphorothionate binding in kindled rat hippocampus shows different changes in CA1 area and fascia dentata.

Abstract

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)

• Authors: M N Titulaer, W Kamphuis, F H Lopes da Silva
• Journal: Neuroscience (Neuroscience) Vol. 66 Issue 3 Pg. 547-54 (Jun 1995) ISSN: 0306-4522 [Print] United States
• PMID: 7644019 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Bridged Bicyclo Compounds
• Bridged Bicyclo Compounds, Heterocyclic
• Chloride Channels
• Convulsants
• Receptors, GABA-A
• Sulfur Radioisotopes
• tert-butylbicyclophosphorothionate

Topics

• Animals
• Autoradiography (methods)
• Bridged Bicyclo Compounds (metabolism)
• Bridged Bicyclo Compounds, Heterocyclic
• Chloride Channels (analysis, metabolism)
• Convulsants (metabolism)
• Electric Stimulation
• Hippocampus (cytology, metabolism, physiology)
• Kindling, Neurologic
• Kinetics
• Male
• Neurons (cytology, metabolism, physiology)
• Organ Specificity
• Pyramidal Cells (cytology, metabolism, physiology)
• Rats
• Rats, Wistar
• Receptors, GABA-A (analysis, metabolism)
• Sulfur Radioisotopes