Distribution of a putative endogenous modulator of the GABAergic system in human brain.
Diazepam binding inhibitor (DBI) is a novel neuropeptide purified from rat, cow, and human brain that allosterically modulates GABAergic transmission by binding to benzodiazepine (BDZ)-recognition sites. Using a specific radioimmunoassay for human DBI, we investigated the distribution of this peptide in different brain areas. We characterized with high-pressure liquid chromatography the DBI immunoreactivity in brain tissue obtained by biopsy and autopsy; we detected one molecular species of DBI in both instances. The regional distribution of DBI in the human brain is similar to that observed in rat brain: high concentrations in cortical and limbic areas, cerebellum, and brainstem, and low concentrations in the basal ganglia. These data suggest a modulatory role for DBI in human brain.
Ferrarese
C
C
Neurological Clinic, University of Milan, Ospedale S. Gerardo, Monza, Italy.
Appollonio
I
I
Frigo
M
M
Piolti
R
R
Tamma
F
F
Frattola
L
L
D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry; D026261:Diazepam Binding Inhibitor; D006801:Humans; D009479:Neuropeptides / Q000032:analysis / Q000378:metabolism*; D014018:Tissue Distribution; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D026261:Diazepam Binding Inhibitor; D009479:Neuropeptides; D005680:gamma-Aminobutyric Acid