Chronic administration of N-methyl-D-aspartate (NMDA) receptor antagonists induced in rats, a facilitation of striatal dopaminergic type D2 transmission: behavioral and biochemical study]

Compared with control rats, rats treated with ketamine (15 mg/kg/day, p.o.) or MK-801 (0.1 to 0.4 mg/kg/day, p.o.) for 6 weeks showed significantly increased: 1) behavioural responses to D2 dopaminergic agents, either agonist or antagonist, 2) striatal D2 receptor mRNA expression, 3) striatal D2 receptor density, without any presynaptic change in dopaminergic or serotoninergic neurotransmission. These results suggest that the functional expression of striatal D2 receptor is postsynaptically regulated by glutamate-triggered events through the NMDA receptor subtype.