Effects of methylphenidate on attentional set-shifting in a genetic model of attention-deficit/hyperactivity disorder.

Background: Although deficits of attentional set-shifting have been reported in individuals with attention deficit/hyperactivity disorder (ADHD), it is rarely examined in animal models.

Methods: This study compared spontaneously hypertensive rats (SHRs; a genetic animal model of ADHD) and Wistar-Kyoto (WKY) and Sprague-Dawley (SD) rats (normoactive control strains), on attentional set-shifting task (ASST) performance. Furthermore, the dose-effects of methylphenidate (MPH) on attentional set-shifting of SHR were investigated.

Effects of different adrenergic blockades on the stress resistance of Wistar rats.

The coordinated responses of the sympathoadreno-medullary (SAM) system and hypothalamic-pituitary-adrenal (HPA) axis could improve the organism's capacity to cope with stress, but its underlying mechanism is still unclear. In the present study, 32 Wistar rats were employed and divided into four groups: control, CUMS, PROP and PRAZ. After the chronic unpredicted mild stress (CUMS) model was built in the latter three groups, all animals were exposed to inescapable footshock.

Effects of adrenergic agents on stress-induced brain microstructural and immunochemical changes in adult male Wistar rats.

This preliminary study aims to explore how adrenergic agents modulate stress response and affect stress-induced behavioral and brain changes in rodents. A total of 40 adult male Wistar rats were subjected to chronic unpredictable mild stress (CUMS) and randomly divided into five groups. At 30 min before daily stress exposure, the rats were intraperitoneally injected with phentolamine (5mg/kg), noradrenalin (1.

Swimming exercise effects on the expression of HSP70 and iNOS in hippocampus and prefrontal cortex in combined stress.

Exercise could play a beneficial role in stress, but its underlying mechanism especially about heat shock protein 70 (HSP70) and inducible nitric oxide synthase (iNOS) in brain has not been fully clarified. Moreover, few studies have investigated swimming exercise and its effects on the combined stress of both chronic and acute stress. In this study we tried to investigate the role of swimming exercise in combined stress and whether its biological mechanism was related to the HSP70 and iNOS in hippocampus and prefrontal cortex.