Validation of chronic mild stress in the Wistar-Kyoto rat as an animal model of treatment-resistant depression
A recent review proposed four criteria for an animal model of treatment-resistant depression (TRD): a phenotypic resemblance to a risk factor for depression; enhanced response to stress; nonresponse to antidepressant drugs and response to treatments effective in TRD, such as deep brain stimulation (DBS) of the prefrontal cortex or ketamine. Chronic mild stress (CMS) provides a valid model of depression; the Wistar-Kyoto (WKY) rat is considered to be nonresponsive to antidepressant drugs. Here, we applied CMS to WKY rats. WKY and Wistar rats were exposed to CMS, then treated with saline, imipramine, citalopram or venlafaxin...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research
Influence of aversive stimulation on haloperidol-induced catalepsy in rats
Catalepsy – an immobile state in which individuals fail to change imposed postures – can be induced by haloperidol. In rats, the pattern of haloperidol-induced catalepsy is very similar to that observed in Parkinson’s disease (PD). As some PD symptoms seem to depend on the patient’s emotional state, and as anxiety disorders are common in PD, it is possible that the central mechanisms regulating emotional and cataleptic states interplay. Previously, we showed that haloperidol impaired contextual-induced alarm calls in rats, without affecting footshock-evoked calls. Here, we evaluated the influence of distinct aversi...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research
The blockade of corticotropin-releasing factor 1 receptor attenuates anxiety-related symptoms and hypothalamus–pituitary–adrenal axis reactivity in mice with mild traumatic brain injury
Recent studies have shown that mild traumatic brain injury (mTBI) is associated with higher risk for anxiety-related disorders. Dysregulation in the hypothalamus–pituitary–adrenal (HPA) axis following mTBI has been proposed to be involved in the development of neurobehavioral abnormalities; however, the underlying mechanisms are largely unknown. The aim of this study was to determine whether the corticotropin-releasing-factor-1 (CRF-1) receptor is involved in the regulation of anxiety-related symptoms in a mouse model of mTBI. Animals with or without mTBI received intracerebroventricular injections of a CRF-1 receptor ...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research
Effects of plus-maze experience and chlordiazepoxide on anxiety-like behavior and serotonin neural activity in the dorsal raphe nucleus in rats
The extent to which rats express anxiety-like behavior on the elevated plus-maze (EPM) depends on their previous maze experience. Open-arm avoidance develops in maze-experienced rats, and is often accompanied by a diminished anxiolytic response to benzodiazepines. Regions of the dorsal raphe nucleus (DRN) were examined in male Sprague-Dawley rats using c-Fos and serotonin immunohistochemistry following a single exposure, a second exposure or no exposure to the EPM. We then examined the effect of the benzodiazepine anxiolytic chlordiazepoxide (CDP, 5 mg/kg) on EPM behavior and DRN neural activity. Enhanced open-arm avoida...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research
Edaravone prevents memory impairment in an animal model of post-traumatic distress
In conclusion, edaravone ameliorated oxidative stress and cognitive impairment associated with a PTSD model, probably by supporting antioxidant mechanism in the hippocampus. (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research
Stress and the gut microbiota-brain axis
In conclusion, the influence of stress on gut microbiota and gut microbiota on stress modulation is clear for different stressors, but although the preclinical evidence is so extensive, the clinical evidence is more limited. A better understanding of the mechanism underlying stress modulation through the microbiota may open new avenues for the design of therapeutics that could boost the pursued clinical benefits. These new designs should not only focus on stress but also on stress-related disorders such as anxiety and depression, in both healthy individuals and different populations. (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
The ‘Yin’ and the ‘Yang’ of the kynurenine pathway: excitotoxicity and neuroprotection imbalance in stress-induced disorders
The amino-acid tryptophan (TRY) is converted into kynurenine (KYN) and subsequent metabolites by the tryptophan/catabolites (TRY/CAT) pathway (kynurenine pathway). ‘Excito-toxic’ and ‘neuro-protective’ metabolites are produced, which modulate the glutamatergic neurotransmission. The TRY/CAT pathway is activated by hypothalamic–pituitary–adrenal endocrine induction during stress by corticoids hormones, and the excitotoxic branch of the TRY/CAT pathway is activated by proinflammatory cytokines. During stress and major depressive disorders, it is generally accepted that inflammation induces an imbalance toward the...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
Serotonin 2A receptors are a stress response system: implications for post-traumatic stress disorder
Serotonin, one of the first neurotransmitters to be identified, is an evolutionarily old molecule that is highly conserved across the animal kingdom, and widely used throughout the brain. Despite this, ascribing a specific set of functions to brain serotonin and its receptors has been difficult and controversial. The 2A subtype of serotonin receptors (5-HT2A receptor) is the major excitatory serotonin receptor in the brain and has been linked to the effects of drugs that produce profound sensory and cognitive changes. Numerous studies have shown that this receptor is upregulated by a broad variety of stressors, and have re...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
Animal models of post-traumatic stress disorder and novel treatment targets
Understanding the neurobiological basis of post-traumatic stress disorder (PTSD) is fundamental to accurately diagnose this neuropathology and offer appropriate treatment options to patients. The lack of pharmacological effects, too often observed with the most currently used drugs, the selective serotonin reuptake inhibitors (SSRIs), makes even more urgent the discovery of new pharmacological approaches. Reliable animal models of PTSD are difficult to establish because of the present limited understanding of the PTSD heterogeneity and of the influence of various environmental factors that trigger the disorder in humans. W...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
Animal models of liability to post-traumatic stress disorder: going beyond fear memory
In this review, we advocate a dimensional approach on the basis of candidate endophenotypes to the development of animal models of post-traumatic stress disorder (PTSD) capable of including genetic liability factors, variations in symptoms profile and underlying neurobiological mechanisms, and specific comorbidities. Results from the clinical literature pointed to two candidate endophenotypes of PTSD: low sensory gating and high waiting impulsivity. Findings of comparative studies in mice of two inbred strains characterized by different expressions of the two candidate endophenotypes showed different strain-specific neural...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
Stress reactivity after traumatic brain injury: implications for comorbid post-traumatic stress disorder
We present the hypothesis that altered stress reactivity as a result of brain injury impacts the amygdala and defense systems to be vulnerable to increased fear and PTSD development from traumatic stress. Identifying biological mechanisms that underlie this vulnerability, such as dysregulated HPA axis function, may lead to better targeted treatments and preventive measures to support psychological health after TBI. (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
The predator odor avoidance model of post-traumatic stress disorder in rats
Individuals with post-traumatic stress disorder avoid trauma-related stimuli and exhibit blunted hypothalamic–pituitary–adrenal axis response at the time of trauma. Our laboratory uses predator odor (i.e. bobcat urine) stress to divide adult Wistar rats into groups that exhibit high (avoiders) or low (nonavoiders) avoidance of a predator odor-paired context, modeling the fact that not all humans exposed to traumatic events develop psychiatric conditions. Male avoiders exhibit lower body weight gain after stress, as well as extinction-resistant avoidance that persists after a second stress exposure. These animals also s...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research
Announcement of special issue for 2020: The behavioural pharmacology of opioids
No abstract available (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: ANNOUNCEMENT Source Type: research
The behavioural pharmacology of stress-related disorders
No abstract available (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: EDITORIAL Source Type: research
Sex still matters: has the prevalence of male-only studies of drug effects on rodent behaviour changed during the past decade?
During the past 10 years, for a number of biomedical disciplines, including behavioural pharmacology, there have been appeals to include both sexes in animal studies of processes that are not sex specific. In 2007, a survey of experimental studies of drug or other chemical effects on rodent behaviour, published in five prominent journals over 20 months (February 2005 to September 2006, inclusive), revealed that 85% of these conducted with rats and 78% of these conducted with mice involved males only. This was in spite of the evidence of sex differences in responsiveness to an increasing number of compounds. To see if the s...
Source: Behavioural Pharmacology - January 12, 2019 Category: Drugs & Pharmacology Tags: COMMENTARY Source Type: research
