•Neuronal activities to acute exercise at different intensities were examined.•Changes in anxiety- and depressive-like behaviors by acute exercise were assessed.•Acute exercise with mild or low ...stress induces antidepressant/anxiolytic effects.
Accumulating evidence suggests that physical exercise can reduce and prevent the incidence of stress-related psychiatric disorders, including depression and anxiety. Activation of serotonin (5-HT) neurons in the dorsal raphe nucleus (DRN) is implicated in antidepressant/anxiolytic properties. In addition, the incidence and symptoms of these disorders may involve dysregulation of the hypothalamic–pituitary–adrenal axis that is initiated by corticotropin-releasing factor (CRF) neurons in the hypothalamic paraventricular nucleus (PVN). Thus, it is possible that physical exercise produces its antidepressant/anxiolytic effects by affecting these neuronal activities. However, the effects of acute physical exercise at different intensities on these neuronal activation and behavioral changes are still unclear. Here, we examined the activities of 5-HT neurons in the DRN and CRF neurons in the PVN during 30min of treadmill running at different speeds (high speed, 25m/min; low speed, 15m/min; control, only sitting on the treadmill) in male Wistar rats, using c-Fos/5-HT or CRF immunohistochemistry. We also performed the elevated plus maze test and the forced swim test to assess anxiety- and depressive-like behaviors, respectively. Acute treadmill running at low speed, but not high speed, significantly increased c-Fos expression in 5-HT neurons in the DRN compared to the control, whereas high-speed running significantly enhanced c-Fos expression in CRF neurons in the PVN compared with the control and low-speed running. Furthermore, low-speed running resulted in decreased anxiety- and depressive-like behaviors compared with high-speed running. These results suggest that acute physical exercise with mild and low stress can efficiently induce optimal neuronal activation that is involved in the antidepressant/anxiolytic effects.
► We investigated the CRF-containing pathway in yawning accompanied by arousal response. ► Activation of LC and DRN neurons is observed in yawning accompanied by arousal response. ► CRF antagonist ...inhibited the arousal response during yawning. ► CRF antagonist also inhibited the neuronal activation of LC and DRN.
We previously reported that intracerebroventricular (icv) administration of corticotropin-releasing factor (CRF) antagonist attenuates the arousal response during yawning behavior in rats. However, the CRF-related pathway involved in the arousal response during yawning is still unclear. In the present study, we assessed the involvement of the CRF-containing pathway from the hypothalamic paraventricular nucleus (PVN) to the locus coeruleus (LC) and the dorsal raphe nucleus (DRN) in the arousal response during frequent spontaneous yawning, which was induced by several microinjections of l-glutamate into the PVN in anesthetized rats, using c-Fos immunohistochemistry. The PVN stimulation showed significant increases in activation of PVN CRF neurons, LC noradrenalin (NA) neurons and DRN serotonin (5-HT) neurons as well as arousal response during yawning. But icv administration of a CRF receptor antagonist, α-helical CRF (9-41), significantly inhibited the activation of both LC NA neurons and DRN 5-HT neurons except the activation of CRF neurons in the PVN, and significantly suppressed the arousal response during yawning. These results suggest that the CRF-containing pathway from PVN CRF neurons to LC NA neurons and DRN 5-HT neurons can be involved in the arousal response during yawning behavior.
The purpose of this study is to improve learners’ speaking ability by introducing a“flipped classroom” to increase their English-speaking opportunities. By having a “small talk” as a class activity ...for 15 weeks, the participants spent much time for preparing for and rehearsing the small talk in class. As the result, the participants significantly improved their speaking ability measured by the OPIc.
Abstract Background noise (BGN) can affect performance of various tasks as a function of its intensity. Such effects may involve modulation of arousal level during task performance, though the neural ...mechanisms responsible for the intensity-dependence of effects of BGN are still unclear in detail. We examined the effects of BGN (white noise) of various intensities (control, < 40 dB without BGN; 70 dB; 100 dB) during maze task on neuronal activity related to arousal and stress responses using c-Fos immunohistochemistry in rats. Performance (number of errors, time to goal, and number of rearings) during the maze task under 70 dB-BGN, but not 100 dB-BGN, was improved compared with the control condition. In addition, 70 dB-BGN increased c-Fos expression in brain areas responsible for arousal, including mesopontine tegmentum, basal forebrain (BF), locus coeruleus (LC), and cortex, whereas 100 dB-BGN markedly activated neurons in stress-related nuclei, such as the hypothalamic paraventricular nucleus, central nucleus and basolateral nucleus of the amygdala, as well as BF cholinergic neurons, LC neurons, and cortex. These findings suggest that BGN during maze task can induce differential neuronal activation depending on the intensity of BGN in the brain areas relating to arousal and stress responses, which might be involved in maze performance.
It has been suggested that regular physical exercise is beneficial to not only physiological adaptation, but also psychological health through stress reduction, antidepressant / anxiolytic properties ...and improvement in mood. However, since exercise regimens have varied widely across experiments, the optimal form, intensity and duration of exertion for producing the maximal benefits of exercise have yet to be established. Recent neuroscience studies have shown that physical exercise could have a positive impact on the brain, raising the hypothesis that the beneficial effects of physical exercise on psychological health are due to morphological and functional adaptation in the brain, rather than physiological adaptation to physical exercise. For example, it has been shown that physical exercise results in increased neurogenesis or expression of brain-derived neurotrophic factor as well as improved cognitive abilities or reduced stress-induced depressive behavior. Although evidence of the neural and behavioral benefits of physical exercise is accumulating, the influences of different regimens of physical exercise on the brain and behavior remain unclear. This issue aims to outline the effects of physical exercise on pathological conditions with a focus on mood disorders, including depression and anxiety, and consider the neural mechanisms of the antidepressant / anxiolytic effects of physical exercise.
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