Anxiety has become a highly paramount field of research attention in psychopharmacology today. Sundry studies have shown a nitric oxide role in the regulation of anxiety. The goal of the study was to investigate sodium nitroprusside ability to affect anxiety-like behavior in mice and to compare this effect with the standard anxiolytic drug, diazepam, using both plus maze test and light/dark box test. The results revealed that sodium nitroprusside at a dose of 1 mg/kg had a significant effect on the behavior in both of the elevated plus maze test and light/dark test. However, at higher dose (3 mg/kg), it has significantly increased the anxiogenic-like effect in the light/dark box test. Diazepam at a dose of 2 mg/kg increased the time spent in open arms in elevated plus maze test and that in light chambers of light/dark test. These outcomes suggest that a nitric oxide pathway seems to play an important role in anxiety. Furthermore, sodium nitroprusside at a dose of 1 mg/kg showed a nearly anxiolytic ability, when compared with diazepam.
