Abnormalities in the central cholinergic transmitter system of the genetically epilepsy-prone rat.
Seizure-experienced Genetically Epilepsy-prone Rats (GEPRs) have increased acetylcholine content and choline acetyltransferase activity in the thalamus and striatum. These cholinergic differences are accompanied by a slight but statistically significant reduction in acetylcholinesterase activity in the midbrain. In addition, no abnormalities were found in the numbers of specific 3H-QNB binding sites in the striatum, hippocampus, inferior colliculi or cortex. Other work has shown no difference in muscarinic receptor function as measured by carbachol-stimulated inositol-1-phosphate formation. These data suggest a possible presynaptic defect in the striatal and thalamic cholinergic system which may play some role in the seizure-prone state of the GEPR. However, caution must be used in interpreting these cholinergic derangements since more recent findings show no differences in thalamic acetylcholine content in seizure-naive GEPRs. Thus, the original cholinergic abnormalities detected in the seizure-experienced GEPR may be an enduring response to seizure activity.
D000109:Acetylcholine / Q000032:analysis; D000110:Acetylcholinesterase / Q000032:analysis; D000818:Animals; D001923:Brain Chemistry; D002794:Choline / Q000032:analysis; D002795:Choline O-Acetyltransferase / Q000032:analysis; D004827:Epilepsy / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D009435:Synaptic Transmission; D014018:Tissue Distribution
D002795:Choline O-Acetyltransferase; D000110:Acetylcholinesterase; D002794:Choline; D000109:Acetylcholine