Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany.
Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany; Department of Internal Medicine, Helios Kliniken GmbH, Rottweil, Germany; Department of Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany.
Neurosci Lett. 2023 Jan 1;792:136938. doi: 10.1016/j.neulet.2022.136938. Epub 2022 Oct 30.
Research on the peptide phoenixin has increased in recent years and greatly widened the known scope of its functions since its discovery in 2013. Involvement of phoenixin has since been shown in anxiety, food intake, reproduction as well as emotional and immunological stress. To further evaluate its involvement in stress reactions, this study aims to investigate the effects of abdominal surgery, a well-established physical stressor, on the activity of phoenixin-immunoreactive brain nuclei.
Male Sprague-Dawley rats (n = 6/group) were subjected to either an abdominal surgery stress protocol or a sham operation. Animals in the verum group were anesthetized, the abdominal cavity opened and the cecum palpated, followed by closing of the abdomen and recovery. Sham operated animals only received inhalation anesthesia and time for recovery. All animals were subsequently sacrificed and brains processed and evaluated for c-Fos activity as well as phoenixin density.
Compared to control, abdominal surgery significantly increased c-Fos activity in the paraventricular nucleus (PVN, 6.4-fold, p < 0.001), the medial part of the nucleus of the solitary tract (mNTS, 3.8-fold, p < 0.001), raphe pallidus (RPa, 3.6-fold, p < 0.001), supraoptic nucleus (SON, 3.2-fold, p < 0.001), ventrolateral medulla (VLM, also called A1C1, 3.0-fold, p < 0.001), dorsal motor nucleus of vagus (DMN, 2.9-fold, p < 0.001), locus coeruleus (LC, 1.8-fold, p < 0.01) and Edinger-Westphal nucleus (EW, 1.6-fold, p < 0.05), while not significantly altering c-Fos activity in the amygdala (CeM, 1.3-fold, p > 0.05). Phoenixin immunoreactivity was not significantly affected by abdominal surgery (p > 0.05).
The observed abdominal surgery-related increase in activity in phoenixin immunoreactive nuclei compared to sham surgery controls supports the hypothesis of an involvement of phoenixin in stress reactions. Interestingly, various psychological and physical stressors lead to specific changes in activity and immunoreactivity in phoenixin-containing nuclei, giving rise to a stressor-specific involvement of phoenixin.
自 2013 年发现以来，凤凰肽的研究近年来有所增加，其功能范围大大拓宽。此后，凤凰肽参与了焦虑、摄食、生殖以及情绪和免疫应激。为了进一步评估其在应激反应中的作用，本研究旨在探讨腹部手术这一公认的躯体应激源对凤凰肽免疫反应性脑核活动的影响。
雄性 Sprague-Dawley 大鼠（每组 n=6）接受腹部手术应激方案或假手术。真手术组动物接受麻醉，打开腹腔触摸盲肠，然后关闭腹部并恢复。假手术组动物仅接受吸入麻醉和恢复时间。所有动物随后被处死，大脑被处理并评估 c-Fos 活性和凤凰肽密度。
与对照组相比，腹部手术显著增加了室旁核（PVN，6.4 倍，p<0.001）、孤束核内侧部（mNTS，3.8 倍，p<0.001）、苍白球（RPa，3.6 倍，p<0.001）、视上核（SON，3.2 倍，p<0.001）、腹外侧延髓（VLM，也称为 A1C1，3.0 倍，p<0.001）、迷走神经背核（DMN，2.9 倍，p<0.001）、蓝斑（LC，1.8 倍，p<0.01）和 Edinger-Westphal 核（EW，1.6 倍，p<0.05）中的 c-Fos 活性，但杏仁核（CeM，1.3 倍，p>0.05）中的 c-Fos 活性无显著变化。腹部手术对凤凰肽免疫反应性无显著影响（p>0.05）。
与假手术对照组相比，观察到的与腹部手术相关的凤凰肽免疫反应性核中活性增加支持了凤凰肽参与应激反应的假设。有趣的是，各种心理和躯体应激源导致凤凰肽含核中活性和免疫反应性的特定变化，导致凤凰肽的应激源特异性参与。
