مینا مختاری هشتجین

The term of aggression with different meaning applied to wide range of integrative behaviors. Two main classes of aggressive behavior include defensive and offensive. The defensive behavior is tactics for protection of vulnerable parts of body but offensive behaviors is defense against intruders. In the natural state defensive animals can flee from the territory but in restrained condition such as laboratory animals, they show flight, crouching, up right defensive posture. The VTA (Ventral Tegmental Area) with dominant dopaminergic neurons is widely implicated in psychotic disorders. Bupropion as an antidepressant agent is used for smoke cessation widely under FDA approval. The clinical data have showed that it can induce aggressive behavior as side effect. Despite clinical evidence, the mechanism of Bupropion on aggression is not known well. Rats defensive aggression were registered online and offline in control, sham and 3 doses of bupropion. Intra VTA injection was carried out by standard stereotaxic surgery. Aggressive behaviors were only affected by 0.25 mg of bupropion and there were no significant difference between other groups. These data showed that bupropion have complex effect on aggression behavior. Bupropion can inhibit reuptake of dopamine and have effect on VTA neuronal activity for modulation of aggression.

The perinatal effects of antidepressants on the central nervous system (CNS) due to its common usage are important issues in neuroscience researches. Bupropion is an atypical antidepressant that is widely used for smoking cessation. The study of synaptic effects of bupropion can reveal its mechanism for nicotine dependence cessation. In this study the effects of long term administration bupropion during perinatal period on synaptic plasticity (Long Term Potentiating or LTP) in neonatal hippocampus slices were evaluated. Hippocampus slices from 19-25 day old rat pups by using standard brain slices techniques were prepared. Slices preparation were accomplished from three groups, control, normal saline and bupropion-treated (40 mg/Kg, i.p) according to maternal perinatal treatments. To produce LTP, the PB stimulation paradigm was applied and evoked responses were recorded from strata pyramidal of area CA1 following stimulation of Schaffer collaterals. Analysis of data showed that LTP induction parameter (PS amplitude) between normal saline and control groups had no significant difference, however there were significant difference between control and treated groups p<0.05, as well as normal saline and treated groups p <0.01. Long term perinatal administration of bupropion decreased induction and maintenance of LTP in strata pyramidal of area CA1. It seems that the loss of LTP maintenance in bupropion-treated animals is more likely the result of the disruption of cellular processes that they contribute following LTP induction.