Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0848237 (acute stress)
 4,619 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Subjective tinnitus is a phantom sound sensation that does not result from acoustic stimulation and is audible to the affected subject only. Tinnitus-like sensations in animals can be evoked by procedures that also cause tinnitus in humans. In gerbils, we investigated brain activation after systemic application of sodium salicylate or exposure to loud noise, both known to be reliable tinnitus-inductors. Brains were screened for neurons containing the c-fos protein. After salicylate injections, auditory cortex was the only auditory area with consistently increased numbers of immunoreactive neurons compared to controls. Exposure to impulse noise led to prolonged c-fos expression in auditory cortex and dorsal cochlear nucleus. After both manipulations c-fos expression was increased in the amygdala, in thalamic midline, and intralaminar areas, in frontal cortex, as well as in hypothalamic and brainstem regions involved in behavioral and physiological defensive reactions. Activation of these non-auditory areas was attributed to acute stress, to aversive-affective components and autonomous reactions associated with the treatments and a resulting tinnitus. The present findings are in accordance with former results that provided evidence for suppressed activation in auditory midbrain but enhanced activation of the auditory cortex after injecting high doses of salicylate. In addition, our present results provide evidence that acute stress coinciding with a disruption of hearing may evoke activation of the auditory cortex. We interpret these results in favor of our model of central tinnitus generation.
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PMID:Expression of c-fos in auditory and non-auditory brain regions of the gerbil after manipulations that induce tinnitus. 1450 32

Chronic tinnitus is a debilitating condition and often accompanied by anxiety, depression, and sleep disturbance. It has been suggested that sleep disturbance, such as insomnia, may be a risk factor/predictor for tinnitus-related distress and the two conditions may share common neurobiological mechanisms. This study investigated whether acute stress-induced sleep disturbance could increase the susceptibility to acoustic trauma-induced tinnitus in rats. The animals were exposed to unilateral acoustic trauma 24 h before sleep disturbance being induced using the cage exchange method. Tinnitus perception was assessed behaviourally using a conditioned lick suppression paradigm 3 weeks after the acoustic trauma. Changes in the orexin system in the hypothalamus, which plays an important role in maintaining long-lasting arousal, were also examined using immunohistochemistry. Cage exchange resulted in a significant reduction in the number of sleep episodes and acoustic trauma-induced tinnitus with acoustic features similar to a 32 kHz tone at 100 dB. However, sleep disturbance did not exacerbate the perception of tinnitus in rats. Neither tinnitus alone nor tinnitus plus sleep disturbance altered the number of orexin-expressing neurons. The results suggest that acute sleep disturbance does not cause long-term changes in the number of orexin neurons and does not change the perception of tinnitus induced by acoustic trauma in rats.
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PMID:The effects of acute stress-induced sleep disturbance on acoustic trauma-induced tinnitus in rats. 2516 23

Tinnitus is primarily an auditory symptom. Yet not only patients and clinicians, but also current pathophysiological models relate the onset and maintenance of tinnitus to stress. Here physiological and psychological stress reactivity was investigated in 19 patients with subjective chronic tinnitus and 19 comparable healthy controls. All participants underwent five consecutive measurements in one session including three resting conditions and two stress tasks in between (mental arithmetic and concentration on tinnitus/ear noise). Stress reactivity was assessed by heart rate (HR), heart rate variability (HRV) and subjective ratings for each of the five measurements. In patients with tinnitus, mean HR was overall decreased and blunted in response to acute stress induced by mental arithmetic compared to controls. HRV measures did not differ between both groups. Tinnitus sufferers indicated more subjective stress and increased awareness of tinnitus after the mental arithmetic task (during both resting and concentration on tinnitus measurements), but perceived similar levels of stress during mental arithmetic stress. In contrast to controls, HR and HRV were not correlated and also strain reports and physiological data were not associated in tinnitus. Our data show hints for a de-synchronization of physiological and psychological stress reactivity in chronic tinnitus.
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PMID:Stress Reactivity in Chronic Tinnitus. 2813 46