Contributions of animal models to the study of mood disorders

Abstract

Mood disorders are a leading cause of morbidity and mortality, yet their underlying pathophysiology remains unclear. Animal models serve as a powerful tool for investigating the neurobiological mechanisms underlying psychiatric disorders; however, no animal model developed to date can fully mimic the ''corresponding'' human psychiatric disorder. In this scenario, the development of different animal models contributes to our understanding of the neurobiology of these disorders and provides the possibility of preclinical pharmacologic screening. The present review seeks to provide a comprehensive overview of traditional and recent animal models, recapitulating different features and the possible pathologic mechanisms of mood disorders emulated by these models.

Cellular and behavioral effects of lipopolysaccharide treatment are dependent upon neurokinin-1 receptor activation

“…To assess the effect of NK1R antagonism on LPSinduced anhedonic-like behavior, a sucrose preference test was conducted [38][39][40]. Rats (n = 6/group) were provided with one bottle containing 1% (w/v) sucrose solution and one bottle containing water for 2 days to establish a baseline sucrose preference.…”

Insulin-like growth factor 2 mitigates depressive behavior in a rat model of chronic stress

“…Chronic unpredictable stress and repeated restraint stress are the two most important animal models of depression, and both induce hypothalamicepituitaryeadrenal (HPA) axis dysfunction as indicated by alterations in corticosterone levels and changes in the immune system and other pathophysiological aspects found in depressive patients (Valvassori et al, 2013). Some researchers believe that repeated homotypic stressors may lead to habituation but this is not the case with heterotypic stressors (Armario et al, 2008;Armario and Nadal, 2013;Babb et al, 2014).…”

Modeling mania in preclinical settings: A comprehensive review

“…Willner (1984) initially developed a set of validity criteria (Willner, 1984), which were further developed by other groups (Nestler and Hyman, 2010). Briefly, an animal model of a given mental disorder should mimic the manifestations of the equivalent clinical phenomenon (face validity), resemble pathophysiological aspects of the illness (construct validity), and respond to existing clinically successful treatments (predictive validity) (Hamani and Nobrega, 2010, 2012; Nestler and Hyman, 2010; Valvassori et al, 2013; Willner, 1984). Of note, while this terminology was first adopted by Willner and colleagues and later by many others, the definitions of these validity criteria in the field of animal models in general and animal models for neuropsychiatric disorders in particular are much more limited.…”

“…While behavioral responses, such as fear, aggressiveness, irritability, euphoria, and dysphoria may be regarded as subjective components of mania, other manifestations such as locomotor activity and aberrations in circadian rhythms may be considered objective manic-like behaviors. Likewise, other physiological responses may also be measured in preclinical models of mania providing insights on molecular and cellular pathophysiological processes involved in the genesis, persistence, and treatment of BD in humans (Teixeira and Quevedo, 2013; Valvassori et al, 2013; Young et al, 2011a). Recently, the field has witnessed significant advances with the development of novel preclinical models of mania (Dzirasa et al, 2011; Einat, 2014a; Sidor et al, 2015).…”