Epilepsy is a chronic neurological condition characterized by recurrent seizures that affects millions of people worldwide. Comprehension of the complex mechanisms underlying epileptogenesis and seizure generation in temporal lobe epilepsy and other forms of epilepsy cannot be fully acquired in clinical studies with humans. As a result, the use of appropriate animal models is essential. Some of these models replicate the natural history of symptomatic focal epilepsy with an initial epileptogenic insult, which is followed by an apparent latent period and by a subsequent period of chronic spontaneous seizures. Seizures are a combination of electrical and behavioral events that are able to induce chemical, molecular, and anatomic alterations. In this review, we summarize the most frequently used models of chronic epilepsy and models of acute seizures induced by chemoconvulsants, traumatic brain injury, and electrical or sound stimuli. Genetic models of absence seizures and models of seizures and status epilepticus in the immature brain were also examined. Major uses and limitations were highlighted, and neuropathological, behavioral, and neurophysiological similarities and differences between the model and the human equivalent were considered. The quest for seizure mechanisms can provide insights into overall brain functions and consciousness, and animal models of epilepsy will continue to promote the progress of both epilepsy and neurophysiology research.

Schizophrenia is a heterogeneous psychiatric disorder that is poorly treated with current therapies. In this brief review, we provide an update regarding the use of animal models to study schizophrenia in an attempt to understand its aetiology and develop novel therapeutic strategies. Tremendous progress has been made developing and validating rodent models that replicate the aetiologies, brain pathologies, and behavioural abnormalities associated with schizophrenia in humans. Here, models are grouped into 3 categories-developmental, drug induced, and genetic-to reflect the heterogeneous risk factors associated with schizophrenia. Each of these models is associated with varied but overlapping pathophysiology, endophenotypes, behavioural abnormalities, and cognitive impairments. Studying schizophrenia using multiple models will permit an understanding of the core features of the disease, thereby facilitating preclinical research aimed at the development and validation of better pharmacotherapies to alter the progression of schizophrenia or alleviate its debilitating symptoms.

Background: Better treatments for schizophrenia are urgently needed. The therapeutic use of the nitric oxide (NO)-donor sodium nitroprusside (SNP) in patients with schizophrenia has shown promising results. The role of NO in schizophrenia is still unclear, and NO modulation is unexplored in ketamine (KET) animal models to date. In the present study, we compared the behavioral effects of pre-and post-treatment with SNP, glyceryl trinitrate (GTN), and methylene blue (MB) in the acute KET animal model of schizophrenia. The present study was designed to test whether acute SNP, GTN, and MB treatment taken after (therapeutic effect) or before (preventive effect) a single KET injection would influence the behavior of rats in the sucrose preference test, object recognition task and open field.

Abstract-Preconditioning can induce a cascade of cellular events leading to neuroprotection against subsequent brain insults. In this study, we investigated the chronic effects of hypoxic preconditioning on spontaneous recurrent seizures (SRS), neuronal death, and spatial memory performance in rats subjected to pilocarpine (Pilo)-induced status epilepticus (SE). Rats underwent a short hypoxic episode (7% O 2 + 93% N 2 ; 30 min on two consecutive days) preceding a 4-h SE (HSE group). Control groups were rats submitted to SE only (SE), rats subjected to hypoxia only (H) or normoxia-saline (C). Animals were monitored for the occurrence of SRS, and spatial memory performance was evaluated in the radial-arm maze. Hippocampal sections were analyzed for cell death and mossy fiber sprouting at 1 or 60 days after SE. Compared to SE group, HSE had increased SE latency, reduced number of rats with SRS, reduced mossy fiber sprouting at 60 days, and reduced cell death in the hilus and the CA3 region 1 and 60 days after SE. Additionally, HSE rats had better spatial memory performance than SE rats. Our findings indicated that short hypoxic preconditioning preceding SE promotes long-lasting protective effects on neuron survival and spatial memory. Ó

A minha mãe Edna que me viu primeiro, a minha inspiração, que optou ser feliz por me ver brilhar. Hoje voo sozinha, mas minhas asas são você. Minha eterna gratidão ao meu primeiro amor na vida e para sempre o mais importante. Ao meu irmão Ridan pela amizade, confiança, à quem não temo declarar o meu amor. Somos dois e também apenas um, não vivo sem que esteja sempre ao meu lado a melhor parte de mim! VI AGRADECIMENTOS A DEUS pelo direcionamento, conquistas e me fazer chegar até o fim. Fé torna as coisas possíveis e ciência e DEUS se atraem. Ao Prof. Jaime Eduardo Cecílio Hallak sou profundamente grata por sua orientação, atenção, disposição, por caminhar junto e enorme incentivo, exemplo de seriedade e competência científica. À Dra. Ludmyla Kandratavicius sou profundamente grata pela espetacular coorientação, pela competência científica, pelo crescimento acadêmico, suporte, apoio, presença constante do começo ao fim, pela amizade inestimável e para sempre. Ao Prof. João Pereira Leite pelo apoio, suporte e todo conhecimento científico adquirido desde o mestrado. Ao Dr. José Eduardo Peixoto-Santos pelo apoio, incentivo, presença, suporte durante o trabalho, pela amizade valiosa e para sempre À Renata Caldo Scandiuzzi pelos ensinamentos, eficiência, apoio, incentivo, presença, suporte durante todo o trabalho, pela amizade valiosa e para sempre Às Dras. Mariana Raquel Monteiro e Raquel Do-Val da Silva pelo apoio e suporte durante o trabalho e pela grande amizade. Aos Drs. Glen Baker e Serdar Dursun sou profundamente grata por me acolherem na Universidade de Alberta (Canadá) e me proporcionarem conhecimento e crescimento científico. Obrigada pelo acompanhamento no doutorado sanduiche. A Silvana Loturco e Renato Meirelles funcionários do departamento de Neurociências e Ciências do Comportamento sempre disponíveis e atenciosos. À agência de fomentos CAPES pelo apoio financeiro direito e também apoio no doutorado sanduiche para o desenvolvimento desse trabalho. VIII com epilepsia. Além disso, não exacerbou crises e contribuiu para diminuição delas nos animais do modelo de epilepsia e psicose, que apresentou grandes similaridades com o que é encontrado em casos clínicos. Nossos resultados sugerem que o uso do NPS pode ter resultados na melhoria dos sintomas da psicose interictal humana, assim como já observado para a esquizofrenia. Palavras-chave: psicose, epilepsia, comorbidade psiquiátrica, modelo animal, quetamina, pilocarpina, nitroprussiato de sódio.