Effect of no synthesis inhibition on striatal dopamine release and stereotyped behavior induced by a single administration of methamphetamine.

1. The authors performed both microdialysis and behavioral measurement in each of rats, in order to examine effects of nitric oxide synthase inhibitor, N omega-nitro-L-arginine methyl ester (LNAME;30 mg/kg,i.p.) on striatal dopamine (DA) release and stereotypy induced by a single administration of methamphetamine (MA)(4 mg/kg,s.c.), simultaneously. 2. LNAME administered prior to MA significantly decreased level of locomotion-stereotypy rating scores induced by MA. 3. In the same animals, LNAME had no effect on MA-induced striatal DA release. 4. The results suggest that NO synthesis inhibition attenuated MA-induced stereotypy by modulating neuronal process subsequent to activation of postsynaptic DA receptors.