Retrograde transport of [3H]GABA in the striatotegmental system of the pigeon

The method of retrograde transport of gamma-aminobutyric acid (GABA) injected into the nigral complex of the pigeon was used to determine the transmitter-specificity of the striatotegmental projection system in this species. The results indicate that descending GABAergic projections are derived from the nucleus accumbens (Ac), ventral lobus parolfactorius (LPO) and the ventral paleostriatum (VP). In birds VP is considered comparable to the mammalian ventral pallidum/substantia innominata area. These results are interpreted in terms of the similarities and differences of striatal organization in birds, reptiles and mammals.