Iptakalim alleviated the increase of extracellular dopamine and glutamate induced by 1-methyl-4-phenylpyridinium ion in rat striatum

The present study examined the effect of iptakalim (Ipt), a novel ATP-sensitive potassium (KATP) channel opener (KCO), on 1-methyl-4-phenylpyridinium ion (MPP+)-induced dopamine (DA) and glutamate efflux in extracellular fluid of rat striatum, using microdialysis technique. Rats were implanted guide cannula in the striatum and artificial cerebrospinal fluid was infused through a microdialysis probe to detect the level of DA and glutamate in the striatum. MPP+ significantly enhanced the extracellular levels of DA and its metabolites, DOPAC and HVA, as well as glutamate. Application of Ipt (1, 10, 100 μM) concentration-dependently suppressed DA and its metabolites efflux induced by MPP+. Concomitantly, Ipt reduced the increase of extracellular glutamate induced by MPP+. These results suggest that Ipt can regulate DA and glutamate efflux induced by MPP+ in rat striatum.