Expression of long-term potentiation of the striatum in methamphetamine-sensitized rats

We examined the change of corticostriatal glutamatergic neuronal transmissi on in striatal slices of methamphetamine (MAP)-sensitized rats in vitro. Te tanic stimulation induced long-term depression (LTD) of the field potential in the striatum of saline-treated rats. However, it induced long-term pote ntiation (LTP) in the striatum of MAP-sensitized rats. This LTP was signifi cantly suppressed by a N-methyl-D-aspartate (NMDA) receptor antagonist, ami nophosphonovaleric acid (APV). These results suggest that LTP is expressed in the striatum of MAP-sensitized rats, and that NMDA receptors are indispe nsable for the LTP formation. (C) 1999 Elsevier Science Ireland Ltd. All ri ghts reserved.