Xin Liu

University of Jinan (Jinan, China), Chi-nan-shih, Shandong Sheng, China

Are you Xin Liu?

Claim your profile

Publications (4)7.86 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: 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. We found that α(1)-adrenoceptor antagonist prazosin (PRAZ) administration could improve behavior changes, reduce the cellular impairment in brain and inhibit the hyperfunction of HPA axis induced by CUMS exposure. Moreover, it decreased the heat shock protein 70 and inducible nitric oxide synthase expression in different brain areas as subsequently exposed to acute stress. In conclusion, α1-adrenoceptor may play a major role in regulating the coordinated responses between two physiological axes and improve the stress resistance.
    Neuroscience Letters 03/2012; 511(2):95-100. · 2.03 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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 (1.0mg/kg), propranolol (10mg/kg), isoproterenol (0.05 mg/kg) or saline, respectively. Another 8 rats served as normal control and received daily saline injection without stress exposure. Open-field behaviors were tested at 1 day after the end of the 21 days of stress exposure. Blood samples were collected for serum corticosterone measurement. Brain sections containing hippocampus were stained with hematoxylin and eosin (H&E) as well as by immunohistochemistry for heat shock protein 70 (hsp70) and nitric oxide synthase type 2 (nos2) analyses. The experimental results demonstrated that repetitive dosing of noradrenalin, phentolamine, and propranolol during chronic stress might region-dependently attenuate stress-induced microstructural and biochemical changes in the hippocampus, although propranolol intensified stress-induced behavioral changes.
    Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 07/2011; 193(5):418-24. · 1.96 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Although studies have shown that psychological stress has detrimental effects on bronchial asthma, there are few objective data on whether early-life stress, as early postnatal psychosocial environment, has a long-lasting effect on adult asthma and the potential pathophysiologic mechanism. This study aims to examine the effects on immune function and hypothalamic-pituitary-adrenal (HPA) axis responses in adult asthmatic rats that experienced stress in early life and the potential ameliorative effects of music therapy on these parameters. Forty male Wistar rat pups were randomly assigned to the asthma group, the adulthood-stressed asthma group, the childhood-stressed asthma group, the music group, and the control group. Restraint stress and Mozart's Sonata K.448 were applied to ovalbumin (OVA)-induced asthmatic rats to establish psychological stress and music therapy models. The levels of serum corticosterone were examined in both childhood after stress and adulthood after OVA challenge. Immune indicators in blood, lung, and brain tissues were measured after the last OVA challenge. Stress in both childhood and adulthood resulted in increases in leukocyte and eosinophil numbers and serum interleukin (IL)-4 levels. The adulthood-stressed group demonstrated increased corticosterone levels after challenge, whereas the childhood-stressed group showed increased corticosterone concentration in childhood but decreased level in adulthood. Central IL-1beta exhibited a similar tendency. Music group rats showed reduced serum IL-4 and corticosterone. Stress in childhood and adulthood resulted in different HPA axis responsiveness in the exacerbation of markers of asthma. These data provide the first evidence of the long-term normalizing effects of music on asthmatic rats.
    Journal of Asthma 06/2010; 47(5):526-31. · 1.85 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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. 32 Wistar rats were enrolled and divided into four groups: control, CUMS, labetalol and exercise. After the animal model of chronic unpredicted mild stress (CUMS) was built in the latter three groups, all the rats were given the novel acute stress of inescapable footshock. The behavioral changes were measured by open field test. Radioimmunoassay (RIA) was adopted to test the change of serum corticosterone (CORT). The expression of HSP70 and iNOS in hippocampus and prefrontal cortex was analyzed by Western blot. The results demonstrated that swimming exercise could not only improve the behavior changes and protect the function of HPA axis stable in CUMS animals exposed to novel acute stress, but also increase the HSP70 expression and decrease the iNOS expression in hippocampus and prefrontal cortex. In conclusion, swimming exercise could play a beneficial role in combined stress by up-regulating HSP70 level and down-regulating iNOS level in brain.
    Neuroscience Letters 05/2010; 476(2):99-103. · 2.03 Impact Factor