Tryptoline inhibition of serotonin uptake in rat forebrain homogenates.
We have examined the effects of six tryptolines (tetrahydro-beta-carbolines) upon 5-hydroxytryptamine (5-HT) uptake into rat forebrain homogenates. All six were found to be competitive inhibitors of 5-HT uptake. 5-Hydroxytryptoline, the most potent inhibitor, had an inhibitor constant (Ki) of 0.3 mugM. Both 5-hydroxytryptoline and 5-hydroxymethtryptoline were also shown to be relatively selective against 5-HT uptake, being 20 times less potent against norepinephrine uptake and 40 times less potent against dopamine. Since it is possible that tryptolines might be formed as a result of alcohol consumption, these results suggest that it is important to examine the possibilities that such compounds mediate some of the effects of alcohol upon serotonergic pathways.
D000428:Alcohol Drinking; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002243:Carbolines / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D010647:Phenyl Ethers / Q000494:pharmacology; D011437:Propylamines / Q000494:pharmacology; D051381:Rats; D012701:Serotonin / Q000378:metabolism*
D002243:Carbolines; D007211:Indoles; D010647:Phenyl Ethers; D011437:Propylamines; D012701:Serotonin; D004298:Dopamine; D009638:Norepinephrine