The effects of NO are blocked by the NO scavenger carboxy-PTIO. A, Locomotor activity was induced in NMDA (100 μm) in the presence of the NO scavenger carboxy-PTIO (150 μm). B, Equimolar application of DEA/NO failed to increase the locomotor frequency. C, Averaged data from all the experiments showing the failure of DEA/NO to increase the locomotor frequency in the presence of carboxy-PTIO (p > 0.05, n = 4). D, Inhibition of soluble guanylate cyclase with ODQ blocked part of the increase of the DEA/NO-induced increase in the locomotor frequency. The graph represents averaged data from all the experiments and shows a significant block of DEA/NO effect by ODQ (p < 0.02, n = 12).