Comparison of effect of intraperitoneal vs. intra-accumbal injection of memantine on response to acute stress in female NMRI mice

Introduction: In this study, the effect of memantine administration into the nucleus accumbens on the metabolic changes induced by acute stress in female mice was evaluated. Methods: Intra-accumbens unilateral or bilateral canulation was performed. One week after recovery, a group of animals were given memantine (1, 0.5, and 0.1 μg/mouse) five min before stress induction intra-accumbally, and the other group received it (1, 0.5 and 0.1 mg/kg) 30 min before stress intraperitoneally. Food and water intake, weight of fecal material, and the delay time before eating were measured as metabolic parameters after stress induction. Results: Acute stress reduced water and food intake, fecal matter, and the delay time before eating. Intraperitoneal memantine injections augmented the stress effect on water intake, but inhibited its effect on food intake at dose of 0.1 mg/kg and had no impact on defecation. The drug induced anorexia especially at dose of 1 mg/kg. On the other hand, intra-accumbens memantine injections reduced water intake when the drug was injected in the left side. Moreover, memantine injections inhibited or enhanced the effects of stress on water intake, food intake and defecation in a doseand location-dependent manner, and also increased the delay time before eating. Conclusion: Memantine inhibits or enhances the effects of acute stress dose-dependently. In addition, it seems that there is asymmetry in nucleus accumbens response.