A study on benzodiazepine receptor binding in audiogenic seizure-susceptible rats.
Benzodiazepine receptors were investigated in the cerebral cortex, the hippocampus, the brainstem, and the cerebellum of audiogenic seizure (AGS)-susceptible and seizure-resistant (ER) control rats. In AGS-susceptible rats of Sprague-Dawley descent, muscimol (10-6 M and 3 x 10-5 M) activated the binding of 3H-diazepam (0.4 nM) significantly less than in ER-rats. This finding may be strain selective, since it was not observed in AGS-susceptible rats of Wistar descent. Specific binding of the convulsant benzodiazepine receptor ligand methyl 6,7-dimethoxy-4-ethyl carboline-3-carboxylate (3H-DMCM), the benzodiazepine receptor ligand 3H-diazepam and the chloride channel directed cage convulsant t-butylbicyclophosphorothionate 35S-TBPS were not significantly changed in AGS-susceptible as compared to control rats. Our findings indicate that a disturbance at the level of the benzodiazepine receptor/GABA receptor/chloride channel complex is not a likely general aetiological factor for audigenic seizures in rats.
D000161:Acoustic Stimulation; D000818:Animals; D001643:Bridged Bicyclo Compounds / Q000378:metabolism; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002243:Carbolines / Q000378:metabolism; D003292:Convulsants / Q000378:metabolism; D003975:Diazepam / Q000378:metabolism; D005260:Female; D005445:Flunitrazepam / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009118:Muscimol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011963:Receptors, GABA-A / Q000187:drug effects / Q000378:metabolism*; D012640:Seizures / Q000378:metabolism*
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002243:Carbolines; D003292:Convulsants; D011963:Receptors, GABA-A; C034818:methyl 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate; D009118:Muscimol; D005445:Flunitrazepam; C037476:tert-butylbicyclophosphorothionate; D003975:Diazepam