The Effect of Risperidone on the Induction of Psychological Dependence and the Number of Hippocampal Neurons in Adult Male Rats

Psychological dependence on substances is the desire to consume substances or something that has pleasurable effects and produces satisfaction. Various substances cause this dependence. Previous studies indicate the possible effect of risperidone on the brain reward system and the involvement of different receptors in conditioned place preference (CPP). Therefore, the present study was designed with the aim of investigating the effect of risperidone on the induction of psychological dependence and the number of hippocampal neurons. For this study, 40 male Wistar rats with a weight range of 230-280 grams were used. Risperidone was injected intraperitoneally with doses of 1, 2 and 4 mg/kg. At the end of the hippocampus experiments, the animals were taken out and fixed by formalin, then cut and after staining, they were used for histological evaluation and neuronal counting. The results of this study showed that the administration of risperidone with a dose of 2 and 4 mg/kg causes a significant increase in CPP (p < 0.05). Also, in histological evaluation, no neuronal destruction was observed in all risperidone groups (1, 2 and 4 mg/kg). According to the obtained results, it can be concluded that risperidone in higher doses causes an increase in conditioned place preference and learning and dependence and should be considered in treatment.