Effects of intracerebroventricular injection of 7-nitroindazole on depression-like behaviors and nNOS expression in hippocampal of rats

Abstract

Objective To evaluate the effect of intracerebroventricular injection of 7-nitroindazole(7-NI) on the depression-like behaviors in normal rats. Methods According to body weights, 48 SD rats were randomly divided into normal group, model group, sham-operation group and 7-NI groups at different concentrations (n=8). The model group was treated with chronic and unpredictable mild stress. The 7-NI groups received intracerebroventricular injection with 7-NI solutions at different concentrations, once every 3 days for 3 times in total. The sham-operation group was injected with DMSO of the same volume. The rat behaviors were then subjected to the open field test (OFT). The hippocampal nNOS protein levels were detected by Western blot. Results Compared with the normal group((132.47±31.72)m), the total movement distances of model group ((15.04±8.61)m) and 200 nmol/0.5 μl surgery group((18.18±11.82)m)decreased significantly (P 0.05). Conclusion Intracerebroventricular injection 200 nmol/0.5 μl 7-NI solution results in depression-like behaviors and increased the expression of nNOS protein reflexively in rats. Key words: 7-Nitroindazole; Intracerebroventricular injection; Depression; Behavior; nNOS