title: Interaction between Antagonist of Cannabinoid Receptor and Antagonist of Adrenergic Receptor on Anxiety in Male Rat.
abstract: BACKGROUND
  Anxiety is among the most common and treatable mental disorders. Adrenergic and cannabinoid systems have an important role in the neurobiology of anxiety. The elevated plus-maze (EPM) has broadly been used to investigate anxiolytic and anxiogenic compounds. The present study investigated the effects of intraperitoneal (IP) injection of cannabinoid CB1 receptor antagonist (AM251) in the presence of alpha-1 adrenergic antagonist (Prazosin) on rat behavior in the EPM.
  
  
  METHODS
  In this study, the data were obtained from male Wistar rat, which weighing 200- 250 g. Animal behavior in EPM were videotaped and saved in computer for 10 min after IP injection of saline, AM251 (0.3 mg/kg), Prazosin (0.3 mg/kg) and AM251 + Prazosin, subsequently scored for conventional indices of anxiety. During the test period, the number of open and closed arms entries, the percentage of entries into the open arms of the EPM, and the spent time in open and closed arms were recorded. Diazepam was considered as a positive control drug with anxiolytic effect (0.3, 0.6, 1.2 mg/kg).
  
  
  RESULTS
  Diazepam increased the number of open arm entries and the percentage of spent time on the open arms. IP injection of AM251 before EPM trial decreased open arms exploration and open arm entry. Whereas, Prazosin increased open arms exploration and open arm entry. This study showed that both substances in simultaneous injection have conflicting effects on the responses of each of these two compounds in a single injection.
  
  
  CONCLUSIONS
  Injection of CB1 receptor antagonist may have an anxiogenic profile in rat, whereas adrenergic antagonist has an anxiolytic effect. Further investigations are essential for better understanding of anxiolytic and anxiogenic properties and neurobiological mechanisms of action and probable interactions of the two systems.
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Komaki
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran ; Department of Biology, Faculty of Basic Science, Islamic Azad University, Hamadan, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Abdollahzadeh
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Abdolrahman
authors.initials: A
authors.lastname: Sarihi
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Siamak
authors.initials: S
authors.lastname: Shahidi
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Iraj
authors.initials: I
authors.lastname: Salehi
keywords: Adrenergic Antagonist; Anxiety; Cannabinoid Receptor Antagonist; Diazepam; Elevated Plus-maze; Rat