Effects of intrapallidal drugs on hyperactivity induced by nucleus accumbens dopamine receptor stimulation

The effect of manipulating globus pallidus (GP) transmitters on the locomotor hyperactivity induced by administration of the dopamine agonist ADTN in the nucleus accumbens was investigated in rats with permanent intracerebral cannulae. Hyperactivity was antagonized by the GABA agonists muscimol and baclofen and the GABA antagonist bicuculline. Atropine, ADTN and ethylketazocine in GP had no effects on the response. Both morphine and the 5-HT agonist 5-methoxy-N,N-dimethyltryptamine prevented the hyperactivity. The findings emphasize the role of GP GABA in the NA-induced hyperactivity and provide information about the functions of some other GP transmitters.