5-HT4 receptor modulation of acetylcholine outflow in guinea pig brain slices.
The effect of the 5-HT4 agonist, BIMU-8 was studied on [3H]choline outflow in guinea pig brain slices and synaptosomes. BIMU-8 did not modify [3H]choline efflux in slices kept at rest, but increased [3H]choline outflow in electrically stimulated slices of cerebral cortex (CC), hippocampus (hip) and nucleus basalis magnocellularis (nbm). This effect was prevented by the selective 5-HT4 antagonist, GR 125487. Conversely, BIMU-8 did not affect [3H]choline efflux in hippocampal synaptosomes depolarized with KCl 20 mM. These results provide evidence that BIMU-8 increases the electrically triggered [3H]choline efflux in CC, hip and nbm slices. A possible role of 5-HT4 agonists in memory and learning diseases is suggested.
Siniscalchi
A
A
Department of Clinical and Experimental Medicine, University of Ferrara, Italy.
Badini
I
I
Beani
L
L
Bianchi
C
C
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology; D001921:Brain / Q000378:metabolism*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002794:Choline / Q000378:metabolism; D004558:Electric Stimulation; D004594:Electrophysiology; D005260:Female; D006168:Guinea Pigs; D006624:Hippocampus / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D011189:Potassium Chloride / Q000494:pharmacology; D011985:Receptors, Serotonin / Q000502:physiology*; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology
D001562:Benzimidazoles; D019086:Bridged Bicyclo Compounds, Heterocyclic; D011985:Receptors, Serotonin; C070189:(endo-N-8-methyl-8-azabicyclo-(3.2.1)oct-3-yl)-2,3-dihydro-3-isopropyl-2-oxo-1H-benzimidazol-1-carboxamide; D011189:Potassium Chloride; D002794:Choline; D000109:Acetylcholine