ABSTRACT
The role of parental morphine exposure before gestation on mood disorder in the offspring was well described. Besides, physical activity can improve the symptoms of mood disorders. So, the current study aimed to investigate the role of physical activity on depressive and OCD-like behaviors induced by parental morphine exposure. 40 male and 40 female Wistar rats (60-days old) received morphine for consecutive 10 days and were drug-free for 10 days. They were prepared for mating either with a morphine-abstinent or with a drug-naïve rat. The adult male offspring were divided into two groups as follows: (1) those that were subjected to treadmill exercise for three weeks (3-days each week), and (2) those without exercise. Also, the offspring were subjected to forced swimming and marble-burying tests. The levels of 5-HT3 receptor (R), D1, and D2 dopamine receptor (DR) were evaluated as well as the level of monoamine oxidase-B (MAO-B) in the prefrontal cortex (PFC). Results showed that exercise improved depressive and OCD-like behaviors in the offspring of morphine-abstinent rats. Western blotting data revealed that the levels of 5-HT3R, D1DR, D2DR, and MAO-B in the PFC increased in the offspring of morphine-abstinent rats compared to the control. However, it was shown that treadmill exercise decreases the levels of 5-HT3R, MAO-B, and D2DR. Morphine exposure, even before conception, could affect the behaviors in the offspring. Besides, the molecular changes were also detected in the brain. We found that mild physical activity might modulate OCD and depressive-like behavior in the offspring of morphine-abstinent rats by decreasing the levels of 5-HT3R, D2DR, and MAO-B located in the PFC.
