Effects of meta-chlorophenylpiperazine (mCPP) on grooming and spontaneous alternation in rats: influences of sex and the estral cycle

• Grant number: 19/04351-9
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): June 01, 2019
• Effective date (End): July 31, 2021
• Field of knowledge: Humanities - Psychology - Physiological Psychology
• Principal Investigator: Amanda Ribeiro de Oliveira
• Grantee: Leticia Mitsuko Taguchi
• Host Institution: Centro de Educação e Ciências Humanas (CECH). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Obsessive-Compulsive Disorder (OCD) is characterized by obsessions and/or compulsions that cause great suffering to patients, who feel the need to perform recurrent and persistent ritualistic actions. The underlying neural basis of OCD needs to be better investigated, for exempla by considering the important differences in prevalence, severity and symptomatology between men and women. By using the serotonergic agonist mCPP as a tool to explore the relationship between serotonergic transmission and OCD, the present study aims to contribute in the standardization of a promising animal model, with the objective of evaluating the effects of acute and repeated administration of mCPP on grooming and spontaneous alternation. For this purpose, male and female (proestrus and late diestrus) Wistar rats will receive either intraperitoneally saline or mCPP at doses of 0.1, 0.5 or 1.0 mg/kg, acutely (Experiment 1) or repeated (Experiment 2). The animals will have their grooming behavior evaluated and, in the sequence, will be submitted to the spontaneous alternation test. In Experiment 3, chronic administration of fluoxetine (21 days, 10 or 20 mg/kg) will be used in an attempt to block the effects of mCPP observed in experiments 1 and 2. It is expected that: a) both acute and repeated administration of mCPP exacerbates grooming behavior and impairs spontaneous alternation, but with more robust effects for repeated administration; b) females in the late diestrus phase show the spontaneous alternation behavior more susceptible to the effects of mCPP treatment; and c) chronic administration of fluoxetine blocks the effects produced by mCPP in both grooming and spontaneous alternation. Findings in this direction would indicate that this would be a more promising animal model for OCD studies. (AU)