Fig. 4

M8I, an MMP8 inhibitor, attenuates ouabain-induced manic-like behavior in mice. A This illustration outlines the timeline for the experimental procedures. B Representative images depict the exploratory behavior of the mouse in the open field. C The distance traveled in the open field reflects the mice’s movement. D The time spent immobile indicates periods when the mice were not moving. E The time spent in the inner area of the open field test measures anxiety-related behavior. F Representative images show extreme behavior testing in tail-suspension assay. G Quantitative data from (F) reveals a decrease in immobility time in ouabain-injected mice compared to control or M8I-treated mice. These tests were conducted on day 7 after ouabain was injected into mice via ICV injection. Intraperitoneal injection of M8I (5 mg/kg) began seven days before ouabain injection and continued until the open field test and tail-suspension assay. Quantitative data is presented as means ± SEM; N = 8; analyzed using two-way ANOVA followed by Tukey’s multiple comparisons test, **p < 0.01 and ***p < 0.001