Serotonin agonists reduce dopamine synthesis in the striatum only when the impulse flow of nigro-striatal neurons is intact.
U Spampinato, E Esposito, R Samanin
Journal of Neurochemistry September 1, 1985 DOI: 10.1111/j.1471-4159.1985.tb04092.x (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Population | Rats |
| Interventions | 5-MeO-DMT CPP apomorphine serotonin |
| Dose | 5 mg/kg i.p. 5-MeO-DMT, 2.5 mg/kg i.p. CPP, 2 mg/kg i.p. apomorphine, 10 micrograms in 0.5 microliter serotonin |
| Topics | Serotonin |
| Citations | 36 |
| Key findings | Serotonin agonists reduce dopamine synthesis in the rat striatum only when dopamine neuron impulse flow is intact, suggesting an indirect mechanism. |
Abstract
The effects of 5-methoxy-N, N-dimethyltryptamine (5-MeO-DMT) and m-chlorophenylpiperazine (CPP), two 5-hydroxytryptamine (5-HT, serotonin) agonists, on the accumulation of 3,4-dihydroxyphenylalanine (DOPA] were studied in the striatum of rats treated with gamma-butyrolactone (GBL). Unlike 2 mg/kg i.p. apomorphine, neither 5 mg/kg i.p. 5-MeO-DMT nor 2.5 mg/kg i.p. CPP significantly reduced the GBL-induced increase in DOPA accumulation in the striatum. 5-MeO-DMT and CPP significantly reduced DOPA accumulation in animals that had received the aromatic amino acid decarboxylase inhibitor Ro 4-4602 but not GBL. 5-HT (10 micrograms in 0.5 microliter) injected in the substantia nigra, pars compacta, like GBL, significantly increased Ro 4-4602-induced accumulation of DOPA in the striatum. The data indicate that 5-HT agonists can reduce 3,4-dihydroxyphenylethylamine (DA, dopamine) synthesis in the striatum of rats only when the impulse flow of DA neurons is intact. An indirect effect through mechanisms controlling DA synthesis in the striatum, for instance cholinergic and GABA-ergic neurons, is suggested.