Dissociation of locomotor and conditioned place preference responses following manipulation of GABA-A and AMPA receptors in ventral pallidum.

1. This study examined the roles of GABAergic and glutamatergic neurotransmission in ventral pallidum (VP) in conditioned place preference and locomotor activity. 2. Picrotoxin (0.1 microgram), a GABA antagonist, and (+/-)alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA; 0.14 microgram), a non-NMDA glutamatergic agonist, were injected bilaterally into VP through implanted cannulae. 3. Both drugs produced a robust increase in locomotion, but neither produced conditioned place preference. 4. These results suggest a dissociation of locomotor activity and reward at the level of ventral pallidum. In addition, it was argued that the GABAergic projection from nucleus accumbens to ventral pallidum may not be involved in the processing of reward initiated from dopaminergic activation in nucleus accumbens.