Evidence for a gamma-hydroxybutyrate (GHB) uptake by rat brain synaptic vesicles.
gamma-Hydroxybutyrate (GHB) is an endogenous metabolite of mammalian brain which is derived from GABA. Much evidence favours its role as an endogenous neuromodulator, synthesized, stored and released at particular synapses expressing specific receptors. One key step for GHB involvement in neurotransmission is its uptake by a specific population of synaptic vesicles. We demonstrate that this specific uptake exists in a crude synaptic vesicle pool obtained from rat brain. The kinetic parameters and the pharmacology of this transport are in favour of an active vesicular uptake system for GHB via the vesicular inhibitory amino acid transporter. This result supports the idea that GABA and GHB accumulate together and are coliberated in some GABAergic synapses of the rat brain, where GHB acts as a modulatory factor for the activity of these synapses following stimulation of specific receptors.
Muller
Claude
C
Institut de Chimie Biologique and INSERM U-338, Strasbourg, France.
Viry
Sandrine
S
Miehe
Monique
M
Andriamampandry
Christian
C
Aunis
Dominique
D
Maitre
Michel
M
D026905:Amino Acid Transport Systems; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects / Q000502:physiology; D001923:Brain Chemistry; D002352:Carrier Proteins / Q000378:metabolism; D005998:Glycine / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D009550:Nigericin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012978:Sodium Oxybate / Q000378:metabolism* / Q000493:pharmacokinetics; D013572:Synaptic Vesicles / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D014634:Valinomycin / Q000494:pharmacology; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; D033921:Vesicular Transport Proteins; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D026905:Amino Acid Transport Systems; D002352:Carrier Proteins; D007476:Ionophores; C118623:Slc32a1 protein, rat; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; D033921:Vesicular Transport Proteins; D014634:Valinomycin; D005680:gamma-Aminobutyric Acid; D012978:Sodium Oxybate; D009550:Nigericin; D005998:Glycine