Modifications in muscarinic, dopaminergic and serotonergic receptors concentrations in the hippocampus and striatum of epileptic rats

• Published in: Life sciences (1973) Vol. 78; no. 3; pp. 253 - 258
• Main Authors: de Freitas, Rivelilson Mendes, Aguiar, Lissiana M.V., Vasconcelos, Silvânia M.M., Sousa, Francisca C.F., Viana, Glauce S.B., Fonteles, Marta M.F.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 05.12.2005
• Subjects: Animals; Behavior, Animal - drug effects; Behavior, Animal - physiology; Corpus Striatum - metabolism; Disease Models, Animal; Dopaminergic; Epilepsy - chemically induced; Epilepsy - metabolism; Epilepsy - physiopathology; Hippocampus - metabolism; Male; Muscarinic; Pilocarpine; Pilocarpine - toxicity; Rats; Rats, Wistar; Receptors, Dopamine - metabolism; Receptors, Muscarinic - metabolism; Receptors, Serotonin - metabolism; Serotonergic; Status epilepticus; Serotonergic; Pilocarpine; Muscarinic; Status epilepticus; Dopaminergic
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2005.04.045

The present study was undertaken in order to investigate the muscarinic (M 1), dopaminergic (D 1 and D 2) and serotonergic (5-HT 2) receptors densities in hippocampus and striatum of Wistar rats after status epilepticus (SE) induced by pilocarpine. The control group was treated with 0.9% saline. An other group of rats received pilocarpine (400 mg/kg, s.c.) and both groups were sacrificed 1 h after treatment. The results have shown that pilocarpine administration and resulting SE produced a downregulation of M 1 receptor in hippocampus (41%) and striatum (51%) and an increase in the dissociation constant ( K d) values in striatum (42%) alone. In both areas the 5-HT 2 receptor density remained unaltered, but a reduction (50%) and an increase (15%) in the K d values were detected in striatum and hippocampus, respectively. D 1 and D 2 receptor densities in hippocampus and striatum remained unaltered meanwhile K d values for D 1 receptor declined significantly, 33% in hippocampus and 26% in striatum. Similarly, K d values for D 2 decreased 55% in hippocampus and 52% in striatum. From the preceding results, it is clear that there is a possible relation between alterations in muscarinic receptor density and others systems studied as well as they suggest that changes in dissociation constant can be responsible for the establishment of pilocarpine-induced SE by altering the affinity of neurotransmitters such as acetylcholine, dopamine and serotonine.