Reduction of A1 adenosine receptors in rat hippocampus after kainic acid-induced limbic seizures.
In a temporal lobe epilepsy (TLE) model induced by kainic acid (KA), we examined the effect of limbic seizures on A1 adenosine receptor distribution in hippocampus and cortex. By using quantitative autoradiography, we determined a progressive decrease in A1 receptor density in CA1 and CA3 regions of hippocampus, which coincided in time with the degenerating process of hippocampal pyramidal cells. This result indicates that a great amount of A1 receptors are located postsynaptically on pyramidal cell dendrites. No difference in A1 receptor density was observed in the inner compared to the outer molecular layer of dentate gyrus, or in the infrapyramidal band compared to the outer layer of stratum oriens of CA3. This could indicate that the newly sprouted mossy fiber glutamatergic terminals do not contain A1 receptors, thus lacking a restrain in the release of glutamate.
Ekonomou
A
A
Department of Physiology, School of Medicine, University of Patras, 265 00, Patras, Greece.
Sperk
G
G
Kostopoulos
G
G
Angelatou
F
F
D000241:Adenosine / Q000378:metabolism; D000818:Animals; D004195:Disease Models, Animal; D004833:Epilepsy, Temporal Lobe / Q000378:metabolism* / Q000503:physiopathology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism*; D007608:Kainic Acid / Q000009:adverse effects; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley; D018047:Receptors, Purinergic P1 / Q000187:drug effects* / Q000378:metabolism*; D012640:Seizures / Q000139:chemically induced* / Q000503:physiopathology*; D013003:Somatosensory Cortex / Q000187:drug effects / Q000378:metabolism
D018047:Receptors, Purinergic P1; D000241:Adenosine; D007608:Kainic Acid