title: An Experimental Study to Evaluate the Effect of Memantine in Animal Models of Anxiety in Swiss Albino Mice.
abstract: BACKGROUND
  Due to the adverse effects produced by the present conventional medicines for anxiety disorders, research for newer drugs is still desirable. From the literature it is evident that NMDA receptors play a key role in animal models of anxiety.
  
  
  OBJECTIVE
  The present study is done to evaluate the antianxiety effect of memantine in swiss albino mice.
  
  
  METHODS
  The experimental study was conducted from November 2014 to January 2015. Animals were divided into four groups. Twelve mice were randomly allotted in each group. Animals in the first group received normal saline as a control 10ml/kg, lorazepam 0.5mg/kg was administered to second group, memantine 3mg/kg as a test drug was given to the third group and memantine 3mg/kg + lorazepam 0.5mg/kg was administered to the fourth group. All the drugs were given for 7 consecutive days by intraperitoneal route.
  
  
  RESULTS
  Results were analyzed by one-way ANOVA followed by Post-hoc Tukey's test. On the 1(st) day, memantine treated group did not show statistical significant anxiolytic effect in both the behavioural paradigms when compared to control group. On the 8(th) day, the animals showed significant decrease p<0.001 in step down latency period in shock free zone (185.4±3.87 Vs 278.3±5.49), significant increase p<0.001 in step down errors (6.8±0.78 Vs 1.4±0.19) and significant increase p<0.001 in total time spent in shock zone (32.1±2.22 Vs 5.6±0.6). In open field test, on 8(th) day the animals treated with memantine when compared to control group, showed significant increase p<0.001 in number of squares crossed (112.7± 2.69 Vs 83.2±2.96), time spent in central square (11.5±1.26 Vs 3.4±0.65), no. of rearings (32.4±2.61 Vs 17±1.81) and significant decrease p<0.001 in freezing time (15.2±1.12 Vs 20.2±2.29). Memantine showed synergistic antianxiety effect when combined with lorazepam.
  
  
  CONCLUSIONS
  Memantine showed significant anxiolytic effect in open field and passive avoidance response tests which are commonly used experimental models to assess anxiety states in animals.
authors.affiliation: Assistant Professor, Department of Pharmacology, MVJ Medical College & Research Hospital , Bangalore, India .
authors.forename: Harish G
authors.initials: HG
authors.lastname: Bagewadi
authors.affiliation: Professor, Department of Pharmacology, MVJ Medical College & Research Hospital , Bangalore, India .
authors.forename: Afzal Khan
authors.initials: AK
authors.lastname: Ak
authors.affiliation: Professor, Department of Pharmacology, MVJ Medical College & Research Hospital , Bangalore, India .
authors.forename: Rekha M
authors.initials: RM
authors.lastname: Shivaramegowda
keywords: Anti-anxiety; Lorazepam; Open field test; Passive avoidance test