No abstract

Accumulating evidence from different animal models has contributed to the understanding of the bidirectional comorbidity associations between the epileptic condition and behavioral abnormalities. A strain of animals inbred to enhance seizure predisposition to high-intensity sound stimulation, the Wistar audiogenic rat (WAR), underwent several behavioral tests: forced swim test (FST), open-field test (OFT), sucrose preference test (SPT), elevated plus maze (EPM), social preference (SP), marble burying test (MBT), inhibitory avoidance (IAT), and two-way active avoidance (TWAA). The choice of tests aimed to investigate the correlation between underlying circuits believed to be participating in both WAR's innate susceptibility to sound-triggered seizures and the neurobiological substrates associated with test performance. Comparing WAR with its Wistar counterpart (i.e., resistant to audiogenic seizures) showed that WARs present behavioral despair traits (e.g., increased FST immobility) but no evidence of anhedonic behavior (e.g., increased sucrose consumption in SPT) or social impairment (e.g., no difference regarding juvenile exploration in SP). In addition, tests suggested that WARs are unable to properly evaluate degrees of aversiveness (e.g., performance on OFT, EPM, MBT, IAT, and TWAA). The particularities of the WAR model opens new venues to further untangle the neurobiology underlying the co-morbidity of behavioral disorders and epilepsy. This article is part of a Special Issue entitled "Genetic and Reflex Epilepsies, Audiogenic Seizures and Strains: From Experimental Models to the Clinic".

The absence of companion may jeopardize mental health in social animals. Here, we tested the hypothesis that social isolation impairs social recognition memory by altering the excitability and the dialog between the olfactory bulb (OB) and the dorsal hippocampus (dHIP). Adult male Swiss mice were kept grouped (GH) or isolated (SI) for 7 days. Social memory (LTM) was evaluated using social recognition test. SI increased glutamate release in the OB, while decreased in the dHIP. Blocking AMPA and NMDA receptors into the OB or activating AMPA into the dHIP rescued LTM in SI mice, suggesting a cause-effect relationship between glutamate levels and LTM impairment. Additionally, during memory retrieval, phase-amplitude coupling between OB and dHIP decreased in SI mice. Our results indicate that SI impaired the glutamatergic signaling and the normal communication between OB and HIP, compromising the persistence of social memory.

No abstract

Animal behavioral paradigms, such as classical conditioning and operant conditioning, are an important tool to study the neural basis of cognition and behavior. These paradigms involve manipulating sensory stimuli in a way that learning processes are induced under controlled experimental conditions. However, the majority of the commercially available equipment did not offer flexibility to manipulate stimuli. Therefore, the development of most versatile devices would allow the study of more complex cognitive functions. The purpose of this work is to present a low-cost, customized and wireless-operated chamber for animal behavior conditioning, based on the joint operation of two microcontroller modules: Arduino Due and ESP8266-12E. Our results showed that the auditory stimulation system allows setting the carrier frequency in the range of 1 Hz up to more than 100 kHz and the sound stimulus can be modulated in amplitude, also over a wide range of frequencies. Likewise, foot-shock could be precisely manipulated regarding its amplitude (from ∼200 μA to ∼1500 μA) and frequency (up to 20 pulses per second). Finally, adult rats exposed to a protocol of cued fear conditioning in our device showed consistent behavioral response and electrophysiological evoked responses in the midbrain auditory pathway. Furthermore, the device developed in the current study represents an open source alternative to develop customized protocols to study fear memory under conditions of varied sensory stimuli.

RESUMO: Este texto trata-se de um relato elaborado a partir de um projeto de extensão, cujo objetivo foi apresentar a alunos do ensino fundamental de uma escola de Diamantina-MG os sistemas morfológicos do corpo humano, correlacionando-os a temas ligados à saúde, hábitos saudáveis e prevenção de doenças. Inicialmente, foi realizado um breve histórico a respeito da Anatomia Humana, bem como a conceituação de educação em saúde. Em seguida, aplicou-se um questionário específico aos sujeitos da pesquisa, o qual direcionou os conteúdos morfológicos que seriam abordados. Em seguida, foram desenvolvidas atividades teóricas e práticas com enfoque nos assuntos ora propostos, no âmbito do Laboratório de Anatomia da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), fornecendo aos participantes uma maior abordagem em ações educativas e preventivas pertinentes ao seu cotidiano. Observou-se que a atividade prática associada ao conteúdo teórico facilitou o processo de ensino-aprendizagem. Quando acrescido o conhecimento sobre danos e ações preventivas, juntamente ao da educação em saúde, minimizou-se a ideia de não vulnerabilidade que os adolescentes possuem. Ainda, espera-se que atividades educativas nesta fase do desenvolvimento dos alunos envolvidos na pesquisa possam trazer benefícios futuros a sua saúde. PALAVRAS-CHAVE: Anatomia humana. Sistemas morfológicos. Saúde. Corpo humano. My body, my fortress: a relationship between anatomy and health ABSTRACT: This project introduced to school students the human body morphologic's systems and correlated them with issues's health, healthy lifestyle and prevention of diseases, based on health education. Initially, there was made a brief history about the Human Anatomy, as well as the concept of health education. Then was applied a specific questionnaire to the research subjects, which directed what morphologic's contents would be explored. Soon after, were developed theoretical and practical activities with a focus on proposed issues, in the Human Anatomy's Laboratory of Federal University of Jequitinhonha and Mucuri's Valleys, providing a greater focus on educational and preventive actions relevant to the daily student. It was observed that the practical activity associated with the theoretical content facilitated the teaching-learning process. When putted damage and preventive actions knowledge together to health education, downplayed the teenagers idea of non-vulnerability that they have. Still, it is expected that educational activities in this subject's stage of development may bring future benefits to their health.

Evidence suggests that the pathophysiology associated with epileptic susceptibility may disturb the functional connectivity of neural circuits and compromise the brain functions, even when seizures are absent. Although memory impairment is a common comorbidity found in patients with epilepsy, it is still unclear whether more caudal structures may play a role in cognitive deficits, particularly in those cases where there is no evidence of hippocampal sclerosis. This work used a genetically selected rat strain for seizure susceptibility (Wistar audiogenic rat, WAR) and distinct behavioral (motor and memory-related tasks) and electrophysiological (inferior colliculus, IC) approaches to access acoustic primary integrative network properties. The IC neural assemblies’ response was evaluated by auditory transient (focusing on bottom-up processing) and steady-state evoked response (ASSR, centering on feedforward and feedback forces over neural circuitry). The results show that WAR displayed no disturbance in motor performance or hippocampus-dependent memory tasks. Nonetheless, WAR animals exhibited significative impairment for auditory fear conditioning (AFC) along with no indicative of IC plastic changes between the pre-conditioning and test phases (ASSR coherence analysis). Furthermore, WAR’s IC response to transient stimuli presented shorter latency and higher amplitude compared with Wistar; and the ASSR analysis showed similar results for WAR and Wistar animals under subthreshold dose of pentylenetetrazol (pro-convulsive drug) for seizure-induction. Our work demonstrated alterations at WAR IC neural network processing, which may explain the associated disturbance on AFC memory.

No abstract