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Hyper-reactivity of HPA axis in Fischer 344 rats is associated with impaired cardiovascular and behavioral adaptation to repeated restraint stress

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    0536856 - FGÚ 2021 RIV GB eng J - Článek v odborném periodiku
    Vodička, Martin - Vavřínová, Anna - Mikulecká, Anna - Zicha, Josef - Behuliak, Michal
    Hyper-reactivity of HPA axis in Fischer 344 rats is associated with impaired cardiovascular and behavioral adaptation to repeated restraint stress.
    Stress-The International Journal on the Biology of Stress. Roč. 23, č. 6 (2020), s. 667-677. E-ISSN 1607-8888
    Grant CEP: GA ČR(CZ) GJ16-10349Y
    Institucionální podpora: RVO:67985823
    Klíčová slova: ACTH * corticosterone * adrenaline * blood pressure * baroreflex * open field
    Kód oboru RIV: ED - Fyziologie
    Obor OECD: Physiology (including cytology)
    Impakt faktor: 3.102, rok: 2019

    Fischer 344 (F344) rats are characterized by the hyper-reactive hypothalamic-pituitary-adrenal axis to stressful stimuli, while Lewis (LEW) rats are considered to be hypo-reactive. We studied stress-induced cardiovascular, neuroendocrine, and behavioral responses of adult male F344 and LEW rats subjected to the single (120 min) or the repeated restraint stress (daily 120 min for 1 week). Mean arterial pressure (MAP) and heart rate (HR) were measured in the restrained rats (n = 7-8 for each group) via a catheter inserted into the femoral artery. Baroreceptor sensitivity was evaluated using NO donor sodium nitroprusside and alpha(1)-adrenoceptor agonist phenylephrine. The plasma levels of adrenocorticotropic hormone (ACTH), corticosterone, aldosterone, and adrenaline were determined before and during the restraint. Exploratory behavior was tested in open field test. F344 rats exerted the augmented stress-induced increase in plasma ACTH, corticosterone, and adrenaline as well as the impaired endocrine adaptation to the repeated stress compared to LEW rats. F344 rats exhibited higher MAP than LEW rats during single and repeated restraint. Moreover, repeatedly restrained F344 showed elevated HR and diminished baroreflex sensitivity. F344 and LEW rats exhibited similar total locomotor activity and the time spent in the center of open field arena, both parameters being decreased by the repeated restraint. The detailed analysis revealed altered pattern of locomotor behavior in F344 rats subjected to repeated restraint. In conclusion, F344 rats showed the impaired endocrine adaptation that resulted in allostatic overload, which might contribute to the impaired cardiovascular and behavioral adaptation to chronic stress observed in this strain.Lay summary F344 rats, characterized by HPA axis hyper-reactivity, exhibited higher blood pressure during restraint than LEW rats. Moreover, repeatedly restrained F344 rats showed elevated heart rate and impaired baroreflex sensitivity. It can be concluded that a poor adaptation to the repeated stress in F344 rats is not only limited to the neuroendocrine response but also has important cardiovascular consequences.
    Trvalý link: http://hdl.handle.net/11104/0314608
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