Evaluation of functional lateralization of the ventral hippocampus: the role of CA1 in different stages of aversive and spatial memory processing

• Grant number: 21/10704-1
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2023
• End date: December 31, 2024
• Field of knowledge: Biological Sciences - Physiology
• Principal Investigator: Luiz Henrique Florindo
• Grantee: Luiz Henrique Florindo
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil
• City of the host institution: São José do Rio Preto
• Associated scholarship(s): 23/01645-7 - Evaluation of the functional lateralization of the ventral hippocampus: the role of CA1 in different stages of aversive and spatial memory processing, BP.TT

Abstract

The hippocampus (HPC) is fundamental for the processing of different types of memory. Studies indicate that there is compartmentalization of functions in the HPC with possible functional lateralization. However, an asymmetric processing is not frequently mentioned, which may impair the observation of neurobiological phenomena. Furthermore, little is known about the contributions of its sub-regions in different stages of memory processing. Thus, this study aims to evaluate the role of the CA1 area of the ventral HPC in the acquisition and/or recall of aversive memory and recall of recent spatial memory; as well as to investigate a possible functional lateralization of this structure. Wistar rats will be submitted to transient inactivations of the CA1 from the ventral HPC through administration of lidocaine (LIDO). Another group of animals will also undergo surgical procedures and some behavioral testing steps; later they will be used to evaluate the activation of c-Fos protein in the area of interest. After surgical recovery, the animals will be exposed to a discriminative avoidance task in the elevated plus maze (PMDAT) or will be submitted to the Morris water maze (MWM). Three experiments will be performed: (i) two exposures in PMDAT with PBS (vehicle) and/or LIDO injection before the first exposure; (ii) two exposures in PMDAT with drug injection before the second exposure and; (iii) training and test in the MWM with drug injection before the retention test. All animals will be exposed to the open field test to evaluate the anxiogenic behavior and possible locomotor impairments. Data will be submitted to a Shapiro-Wilk homogeneity test. Subsequently, will be analyzed with ANOVA (parametric data) or with the Kruskal-Wallis test (non parametric data). For construction of the MWM and PMDAT learning curve, a mixed two-way ANOVA will be performed. The significance level will be accepted when p < 0.05. (AU)