Contingent Social Interaction Does Not Prevent Habituation towards Playback of Pro-Social 50-kHz Calls: Behavioral Responses and Brain Activation Patterns.

Rats, which are highly social animals, are known to communicate using ultrasonic vocalizations (USV) in different frequency ranges. Calls around 50 kHz are related to positive affective states and promote social interactions. Our previous work has shown that the playback of natural 50-kHz USV leads to a strong social approach response toward the sound source, which is related to activation in the nucleus accumbens.

High trait anxiety in mice is associated with impaired extinction in the contextual fear conditioning paradigm.

Trait anxiety is a form of chronic state anxiety that can be part of the individual's personality and one of the individual factors that increase the risk of developing PTSD. To be able to distinguish between trait and state anxiety in animal models might be challenging, since the tests themselves are often anxiogenic. One possible approach is the use of the free exploratory paradigm (FEP), a model that consists of providing the animal the choice to explore both a familiar and a novel environment.

Limited generalizability, pharmacological modulation, and state-dependency of habituation towards pro-social 50-kHz calls in rats.

Communication constitutes a fundamental component of mammalian social behavior. Rats are highly social animals and emit 50-kHz ultrasonic vocalizations (USV), which function as social contact calls. Playback of 50-kHz USV leads to strong and immediate social approach responses in receiver rats, but this response is weak or even absent during repeated 50-kHz USV playback.

Characterization of rat ultrasonic vocalization in the orofacial formalin test: Influence of the social context.

Rats emit ultrasonic vocalizations (USVs) about 22 kHz and 50 kHz sound frequency to communicate the presence of negative or positive emotional states, respectively. The calling behavior may be influenced by several factors, including environmental factors. Likewise, pain behavior can be modulated according to the social context, and also can be transferred to conspecifics through direct observation and/or social interaction.

Posttraumatic stress disorder-type behaviors in streptozotocin-induced diabetic rats can be prevented by prolonged treatment with vitamin E.

Anxiety and stress disorders, such as posttraumatic stress disorder (PTSD) have been described as debilitating comorbidities of diabetes. In the present study, we aimed to investigate anxiety-like behavior and the extinction and generalization of aversive memories in fear conditioning using a streptozotocin-induced model of diabetes (DBT). Moreover, considering that DBT animals present increased oxidative stress in brain areas related to anxiety and memory, we aimed to evaluate the effect of prolonged treatment with antioxidant vitamin E on behavioral parameters of anxiety and fear memory and on the diabetic condition.

Mania-like elevated mood in rats: Enhanced 50-kHz ultrasonic vocalizations after sleep deprivation.

Mania is characterized by elevated drive and mood but animal models of mania have often neglected elevated mood. Ultrasonic vocalizations (USV) of 50-kHz emitted by rats are thought to index the subject's positive affective state. Fifty-kHz USV emission is increased by amphetamine, an effect blocked by lithium administration.

Evaluation of 50-kHz ultrasonic vocalizations in animal models of mania: Ketamine and lisdexamfetamine-induced hyperlocomotion in rats.

Drug-induced hyperlocomotion in rodents is frequently used as a behavioral model for mania. However, the use of locomotor activity as the single parameter in these animal models of mania may pose some limitations for developing new pharmacological treatments. Thus, alternative behavioral markers are required.

Reestablishment of the hyperglycemia to the normal levels seems not to be essential to the anxiolytic-like effect induced by insulin.

Diabetes is a chronic metabolic disease accompanied by several comorbidities, including neuropsychiatric conditions. Since the hyperglycemia appears to be the primary factor involved in diabetic conditions, we examined the effect of insulin treatment in diabetic rats on behavioral responses related to anxiety and aversive memory extinction. For this, normoglycemic (NGL) or streptozotocin-diabetic (DBT) rats were submitted to the elevated T maze (ETM) and the contextual conditioned fear (CCF) tests.

Stretch, Shrink, and Shatter the Rhythms: The Intrinsic Circadian Period in Mania and Depression.

Disturbances in the circadian rhythms have long been associated with depression and mania. Animal models of mania and depression exhibit differential effects upon the intrinsic circadian period and the same occurs with antidepressants and mood stabilizers treatment. The intrinsic circadian period is expressed when there are no time clues or when the light/dark cycle length is beyond the capacity of synchronization.

Depression Associated with Diabetes: From Pathophysiology to Treatment.

Diabetes is a chronic and progressive syndrome commonly associated with several neuropsychiatric comorbities, of which depression is the most studied. The prevalence of depression is about two or three times higher in diabetic patients compared to the general population. It is believed that the diabetes - depression relation may be bidirectional, i.