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Published on: June 18, 2012
Effects of nitric oxide synthase inhibitors 7-NI, L-NAME, and L-NOARG in staircase test
1Department of Pharmacology, Faculty of Medicine, University of Tartu, Estonia. pokk@ut.ee
Background:
The objective of the study was to investigate the effects of the nitric oxide synthase (NOS) inhibitors 7-nitroindazole (7-NI), N(G)-nitro-L-arginine (L-NOARG), and N(G)-nitro-L-arginine methyl ester (L-NAME) on the behavior of mice in the staircase test.
Methods:
NOS inhibitors 7-NI (20-120 mg/kg), L-NOARG (20 and 40 mg/kg), and L-NAME (20 and 40 mg/kg) were administered intraperitoneally (i.p.) 30 min prior to the staircase test. Staircase test consisted of placing a mouse in an enclosed staircase with five steps and recording the number of rearings made and the number of steps climbed during a 3-min period.
Results:
7-NI and L-NOARG did not have a significant effect on the behavior of mice in the staircase test. L-NAME caused a decrease in the number of rearings without changes in the number of steps taken.
Conclusions:
NOS inhibitor L-NAME but not 7-NI or L-NAME induced an anxiolytic effect in the staircase test.
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