Therapeutic effects of exercise, escitalopram and exercise-accompanied escitalopram on brain functions in rats with depression

Introduction: Depression impairs brain functions and memory processes. In a state of depression, escitalopram (as an antidepressant drug) and exercise (as an alternative lifestyle) both affect brain functions. Therefore, this study compared the therapeutic effects of exercise, using escitalopram at two different doses and exercise-accompanied escitalopram on different aspects of brain functions in rats with depression. Methods: Male rats were randomly allocated into nine different groups of control, sham, depression, depression-rest, depression-exercise, depression-escitalopram 10, depression-escitalopram 20, depression-escitalopram 10-exercise and depression-escitalopram 20-exercise. Chronic restraint stress (6h/day, 14 days) was applied to induce depression. The escitalopram injections and treadmill running (1h/day, 14 days) were performed after the stress-induced depression. Moreover, different aspects of brain functions like learning, memory, memory consolidation and locomotor activity were evaluated via the passive avoidance test. Results: The results indicated that depression disrupted learning, memory and memory consolidation. Escitalopram at a dose of 20mg/kg, exercise-accompanied escitalopram 20mg/ kg and only exercise improved them significantly. In rats with depression, escitalopram at a dose of 10mg/kg (with and without exercise) enhanced memory in depression non-significantly. Moreover, the locomotor activity was decreased in groups with exercise-accompanied escitalopram 20mg/kg and exercise compared to only allowing a rest period after depression. Conclusion: Overall, escitalopram 20mg/kg, exercise-accompanied escitalopram 20mg/kg and only exercise had therapeutic effects on memory improvement in subjects with depression. Since the combination of escitalopram 20mg/kg and exercise had a partial additive effect, it was the best treatment protocol for reversing the memory deficits in rats with depression.