Characterization of the interneurons population and in vivo cortical and hippocampal electrophysiological activity of adult rats submitted to neonatal anoxia

• Grant number: 16/17329-3
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): April 01, 2017
• Effective date (End): April 30, 2022
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal researcher: Alexandre Hiroaki Kihara
• Grantee: Juliane Midori Ikebara
• Home Institution: Centro de Matemática, Computação e Cognição (CMCC). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Associated scholarship(s): 19/17677-0 - Effects of neonatal anoxia on spatial memory and place cells activity in adult rodents, BE.EP.DR

Abstract

Neonatal anoxia is the oxygen deprivation at birth , being one of the most common causes of morbidity and mortality in neonates, corresponding to 23% of death worldwide. One of the most vulnerable structures to oxygen deprivation is the hippocampus, which has high metabolic demand and high plasticity capacity. As result of neonatal anoxia, there is a memory and learning deficit that remains in adulthood. One hypotesis is that oxygen deprivation can cause alteration in number of inhibitory interneurons, causing changes in eletrophysiological patterns observed in hippocampal neurons networks. Thus, the aim of this work is to analyze initially if neonatal anoxia causes changes in the balance between excitatory and inhibitory neurons in hippocampal and cortical circuits. Additionally, we will evaluate the hippocampal and cortical electrophysiological patterns in adult rats and correlate how this change can influence the memory deficits caused by anoxia. For this, we assess the number and distribution pattern of interneurons parvalbumin-, calretinin- and calbindia- positives in the hippocampus and cortex by immunofluorescence experiments and 3D image reconstruction by confocal microscopy. Futhermore, we will perform western blotting experiments to quantify the levels of these same proteins. To evaluate the possible electrophysiological activity changes, electrodes will be implanted in adult rats (P60), which will be submitted to the assessment of spatial memory and learning concomitantly the record of the functional electrophysiological patterns. Therefore, we intend to deepen our knowledge of the mechanisms underlying cognitive changes caused by neonatal anoxia. (AU)