γ-aminobutyric acid transporter-1 is involved in anxiety-like behaviors and cognitive function in knockout mice

The aim of the present study was to investigate the effect of γ-aminobutyric acid transporter-1 (GAT-1) on the anxiety-like behaviors and cognitive function in knockout mice. In total, 20 adult male mice were divided into two groups, namely the GAT-1 knockout (GAT-1^-/-) and wild-type (WT) groups. The open field test, elevated 0-maze (EZM) and Morris water maze were used to evaluate changes in anxiety-like behaviors and cognitive function. Compared with the WT mice, GAT-1^-/- mice made more entries and spent a longer time within the central area, traveling a greater distance, during the open field test (P<0.05). The EZM revealed that GAT-1^-/- mice spent more time in the open sectors and made more total entries when compared with the WT mice (P<0.01). Observations from the two tests indicated reduced anxiety-like behaviors in the GAT-1^-/- mice. During the learning session using a Morris water maze, the latency to find the platform was significantly longer in the GAT-1^-/- mice when compared with the WT mice (P<0.01). In addition, during the probe test, the GAT-1^-/- mice spent less time in the target quadrant and more time in the opposite quadrant when compared with the WT mice (P<0.01); thus, the cognitive function in the GAT-1^-/- mice was impaired. Therefore, the results demonstrated that the anxiety-like behaviors were reduced and cognitive function was impaired in GAT-1 knockout mice, indicating that GAT-1 is involved in anxiety and cognitive functions.