Figure 3. Effects of NaHS on the spatial learning and memory dysfunction of STZ-induced diabetic rats in the acquisition and probe phase of Morris water maze test.

Rats were once injected with STZ (40 mg/kg) and treated with NaHS (30 and 100 μmol/kg/d, ip) for 30 days. The cognitive performance of rats was test using the Morris water maze task. (A) Acquisition profiles: rats were submitted to acquisition of an invisible platform placed in a fixed location (target quadrant) with four swims per day during 4 days. (B) Representative swimming tracks of rats searching for the underwater platform at 1^st and 4^th training day. (C, D) One day after finishing the place navigation task (day 5), the platform was removed and the rats were submitted to the probe trial, and the percentage of time spent in the target quadrant (C) and the number of times that the animal crossed the target quadrant platform area (D) were analyzed. The data are expressed as the mean ± S.E.M. (n=7-12). **P< 0.01, ***p< 0.001, versus control group; ^#P< 0.05, ^##P<0.01, ^###P< 0.001, versus STZ-treated alone group.