Neuroscience
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Schizophrenia is one of the most common psychiatric disorders, but despite progress in identifying the genetic factors implicated in its development, the mechanisms underlying its etiology and pathogenesis remain poorly understood. Development of mouse models is critical for expanding our understanding of the causes of schizophrenia. ⋯ We describe and compare the different approaches that are necessitated by diverse susceptibility alleles, and discuss their advantages and drawbacks. Finally, we discuss emerging mouse models, such as second-generation pathophysiology models based on innovative approaches that are facilitated by the information gathered from the current genetic mouse models.
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Major limitations to the pharmacotherapy of Parkinson's disease (PD) are the motor complications resulting from L-DOPA treatment. Abnormal involuntary movements (dyskinesia) affect a majority of the patients after a few years of L-DOPA treatment and can become troublesome and debilitating. Once dyskinesia has debuted, an irreversible process seems to have occurred, and the movement disorder becomes almost impossible to eliminate with adjustments in peroral pharmacotherapy. ⋯ The application of classical 6-hydroxydopamine (6-OHDA) lesion procedures to produce rodent models of dyskinesia has provided the field with more dynamic tools, since the versatility of toxin doses and injection coordinates allows for mimicking different stages of PD. This article will review models developed in non-human primate and rodents to reproduce motor complications induced by dopamine replacement therapy. The recent breakthroughs represented by mouse models and the relevance of rodents in relation to non-human primate models will be discussed.
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Nociception and pain is a large field of both neuroscience and medical research. Over time, various tests and models were developed in rodents to provide tools for fundamental and translational research on the topic. Tests using thermal, mechanical, and chemical stimuli, measures of hyperalgesia and allodynia, models of inflammatory or neuropathic pain, constitute a toolbox available to researchers. ⋯ This aids to further improve the translational value of preclinical research in a field with balanced research efforts between fundamental research, preclinical work, and human studies. This review describes classical tests and models of nociception and pain in rodents. It also presents some recent and ongoing developments in nociceptive tests, recent trends for pain evaluation, and raises the question of the appropriateness between tests, models, and procedures.
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Animal experimentation in the Parkinson's disease (PD) field is a classic example of how the use of animal models to study diseases can have a significant impact on human health. Among the different neurotoxin-based animal models of PD that are presently available, the 6-hydroxydopamine (6-OHDA) and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) models have been established and validated as useful models for the development of therapeutic strategies aimed to treat motor symptoms and to study alterations of the basal ganglia that occur in this disease. The 6-OHDA rat model and the MPTP primate model have contributed enormously to translate animal experimentation into clinical practice, including pharmacological treatments and deep brain stimulation of the subthalamic nucleus. ⋯ At the same time, the lack of any effective neuroprotective strategy for PD is preventing the validation of any one particular model as a screening tool for such neuroprotective strategies. Therefore, it seems that we are trapped in a vicious circle that casts doubt on the suitability of the neurotoxin-based models for this purpose. Here, we discuss how epidemiological data may help to validate a specific model with data linking a lower risk of developing PD with nutritional/consumption habits or with a specific chronic drug therapy.