In male golden hamsters, exposure to social stress during puberty alters aggressive behavior. Interestingly, agonistic behavior undergoes two major transitions during puberty: a decline in attack frequency and a shift from play fighting to adult-like aggression. Based on previous observations, we developed an approach for characterizing offensive responses as play fighting or adult-like. The pr...

Repeated stress has been suggested to underlie learning and memory deficits via the basolateral amygdala (BLA) and the hippocampus; however, the functional contribution of BLA inputs to the hippocampus and their molecular repercussions are not well understood. Here we show that repeated stress is accompanied by generation of the Cdk5 (cyclin-dependent kinase 5)-activator p25, up-regulation and ...

UNLABELLED Stress and the major stress hormone corticosterone induce profound influences in the brain. Altered histone modification and transcriptional dysfunction have been implicated in stress-related mental disorders. We previously found that repeated stress caused an impairment of prefrontal cortex (PFC)-mediated cognitive functions by increasing the ubiquitination and degradation of AMPA-t...

In a previous study we demonstrated that repeated maternal separation impaired spatial memory performance in both male and female adolescent rats. The mechanisms of these cognitive alterations are unknown. In the present study, we examined the effects of repeated maternal separation on oxidative stress in the hippocampus, prefrontal cortex and striatum regions of the brain of the adolescent mal...

Animal and human studies have found that males and females show distinct stress responses. Recent studies suggest the contribution of estrogen in the brain to this sexual dimorphism. Repeated stress has been found to impair cognitive behaviors via suppressing glutamatergic transmission and glutamate receptor surface expression in pyramidal neurons of prefrontal cortex (PFC) in male rats. On the...

Repeated stress induces corticosterone release. However, it is not clear that stress results in further elevation of corticosterone levels, and the roles of released corticosterone to aggravate stress-related symptoms are also not clear. This study investigated whether neuronal modulation was induced in the amygdala after two kinds of stress, that is, such as electric shock and corticosterone i...

The present study was conducted to clarify the protective effect of Brazilian propolis ethanol extract (BPEE) against stress-induced gastric mucosal lesions in rats. The protective effect of BPEE against gastric mucosal lesions in male Wistar rats exposed to water-immersion restraint stress (WIRS) for 6 h was compared between its repeated preadministration (50 mg/kg/day, 7 days) and its single ...

Increasing evidence has shown that oxidative stress may be implicated in chronic stress-induced depression. Several flavonoids with anti-oxidative effects have been proved to be anti-depressive. Myricetin is a well-defined flavonoid with the anti-oxidative, anti-inflammatory, anti-apoptotic, and neuroprotective properties. The aim of the present study is to investigate the possible effects of c...

In male golden hamsters, agonistic behavior matures during puberty, changing from play fighting to adult-like aggression. In addition, this transition is accelerated by repeated social subjugation early in puberty. However, little is known about the development of agonistic behavior in females. In the present study, we compared the development of agonistic behavior in male and female golden ham...

There is extensive evidence that acute stress induces an analgesic response in rats. On the other hand, repeatedly stressed animals may present the opposite effect, i.e., hyperalgesia. Furthermore, exposure to novelty is known to induce antinociception. The effects of repeated restraint stress on nociception after exposure to novelty, as measured by the tail-flick latency (TFL), were studied in...