title: [3H]Acetylcholine and [3H]5-hydroxytryptamine release from rat midbrain slices and the effects of calcium and phenobarbital.
abstract: The K-stimulated release of [3H]ACh from rat midbrain slices prelabeled by incubation with [3H]choline was dependent on extracellular Ca. Phenobarbital inhibited the K-stimulated [3H]ACh release and the IC50 was equal to that found for K-stimulated endogenous ACh release. These results support the suggestion that barbiturates primarily inhibit the Ca-dependent stimulated release of ACh and affect ACh synthesis only indirectly. K-Stimulated release of [3H]5-HT was also inhibited by removing Ca from the medium or by adding phenobarbital which further supports the effects of barbiturates on the depolarization-induced release process. Fluoxetine, an inhibitor of 5-HT uptake, increased the amount of [3H]5-HT found in the medium but did not fully block the uptake of [3H]5-HT in this slice preparation.
mesh_terms: D000109:Acetylcholine / Q000037:antagonists & inhibitors / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology*; D005473:Fluoxetine / Q000494:pharmacology; D008636:Mesencephalon / Q000378:metabolism*; D010634:Phenobarbital / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000378:metabolism
chemical_list: D012702:Serotonin Antagonists; D005473:Fluoxetine; D012701:Serotonin; D000109:Acetylcholine; D011188:Potassium; D002118:Calcium; D010634:Phenobarbital