The Effect of Running on Positive and Negative Slopes on Serotonin Levels in the Hippocampus Tissue of Rats with Alzheimer’s Disease

 Alzheimer’s disease (AD) is a type of age-related disease that affects hippocampus tissue. The AD is a type of amnesiac disorder with dysfunction of the brain in which the patient’s mental ability is gradually dissipated.

 The aim of the present study was to investigate the effect of running on positive and negative slopes on serotonin in the hippocampus tissue of rats with AD.

 In this experimental study, 18 rats were injected with 8 mg/kg trimethyltin chloride (TMT) intra-peritoneally and after being assured of AD, they were divided into three groups of 6 rats, including (1) control, (2) training on positive slope, and (3) training on negative slope. To investigate the effects of AD induction on the serotonin levels, 6 rats were assigned to the healthy control group. Positive training group (at a speed of 16 m/min on positive upward slope) and negative training group (at a speed of 16 m/min on negative downhill slope) ran on the treadmill for eight weeks, five sessions per week and 60 minutes per session. The Shapiro-Wilk, one-way ANOVA with Tukey’s post hoc tests were used to analyze the data (P ≤ 0.05).

 The induction of AD significantly decreased serotonin gene expression levels (P = 0.04); nevertheless, running on positive (P = 0.01) and negative slopes (P = 0.001) significantly increased serotonin gene expression levels in rats with AD.

 Running on positive and negative slopes seems to improve serotonin gene expression levels in the hippocampus tissue of rats with AD.