Trace amines reduce GABA(B) receptor-mediated presynaptic inhibition at GABAergic synapses of the rat substantia nigra pars compacta.
Trace amines (TAs) act in the mammalian brain through amphetamine-like effects and as endogenous agonists of specific receptors. We now show that tyramine and beta-phenylethylamine, in the presence of specific dopamine (DA) receptor antagonists, inhibit the GABA(B)-dependent presynaptic inhibition of GABAergic inputs to midbrain DA neurons. Our results further extend the role of TAs as neuromodulators and propose a novel mechanism by which they modulate DA neurons.
Berretta
Nicola
N
Fondazione Santa Lucia IRCCS, Via Ardeatina 306, 00179 Rome, Italy. n.berretta@hsantalucia.it
Giustizieri
Michela
M
Bernardi
Giorgio
G
Mercuri
Nicola B
NB
D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism; D018755:GABA Agonists / Q000378:metabolism; D009433:Neural Inhibition / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism*; D009924:Organ Culture Techniques; D018408:Patch-Clamp Techniques; D017729:Presynaptic Terminals / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018080:Receptors, GABA-B / Q000378:metabolism*; D018709:Statistics, Nonparametric; D013378:Substantia Nigra / Q000166:cytology / Q000378:metabolism*
D015306:Biogenic Monoamines; D018755:GABA Agonists; D018377:Neurotransmitter Agents; D018080:Receptors, GABA-B; D004298:Dopamine