目的:探讨褪黑素(MLT)对足部电击所致创伤后应激障碍(PTSD)大鼠下丘脑-垂体-肾上腺(HPA)轴的影响。方法:利用足底电击法制备大鼠PTSD模型,通过腹腔注射方法给予治疗组大鼠MLT。通过拒俘反应测试检测大鼠的行为学变化,利用real time RT-...目的:探讨褪黑素(MLT)对足部电击所致创伤后应激障碍(PTSD)大鼠下丘脑-垂体-肾上腺(HPA)轴的影响。方法:利用足底电击法制备大鼠PTSD模型,通过腹腔注射方法给予治疗组大鼠MLT。通过拒俘反应测试检测大鼠的行为学变化,利用real time RT-PCR方法检测下丘脑中促肾上腺皮质激素释放激素(CRH)mRNA的表达,利用酶联免疫吸附试验(ELISA)检测血清中促肾上腺皮质激素(ACTH)、肾上腺素(EPI)和糖皮质激素(GC)的含量。结果:PTSD组大鼠拒俘反应明显(P<0.05),下丘脑中CRH mRNA表达升高(P<0.05),血清中ACTH和EPI明显升高(P<0.05),但是GC水平下降(P<0.05)。MLT治疗后可以明显缓解PTSD大鼠拒俘反应(P<0.05),同时降低下丘脑中CRH mRNA表达(P<0.05),降低血清中ACTH和EPI水平并升高GC的水平(P<0.05)。结论:MLT治疗可缓解PTSD大鼠的症状,并恢复HPA轴的神经内分泌平衡。展开更多
Corticotropin-releasing factor(CRF), which activates the hypothalamic-pituitary-adrenal axis under stress, also has proinflammatory peripheral effects possibly through mast cells. The purpose of this study was to inve...Corticotropin-releasing factor(CRF), which activates the hypothalamic-pituitary-adrenal axis under stress, also has proinflammatory peripheral effects possibly through mast cells. The purpose of this study was to investigate the effect of urocortin (UCN), a 40-amino-acid CRF family peptide, on degranulation and intracellular calcium of rat lung mast cells. The activation and degranulation of mast cells were observed by Toluidine blue staining and transmission electron microscope. The intracellular calcium was investigated using confocal laser scanning microscopy and flow cytometry. The results indicated that all the three different concentrations of UCN(0.1, 1 and 10 mu M) significantly induced the activation and degranulation of rat lung mast cells in vitro. This effect was markedly blocked by selective CRF receptor 1(CRF-R1) antagonist antalarmin, but not by specific CRF receptor 2(CRF-R2) antagonist antisauvagine-30(anti-Svg-30). The results also showed that UCN caused a rapid peak increase inCa2+(i) at point of 300s after UCN treatment, followed by a decrease to a sustained plateau phase. The peak increase inCa2+(i) induced by UCN was significantly inhibited by antalarmin, but not by anti-Svg-30. This effect of UCN onCa2+(i) in rat lung mast cells was also found by flow cytometry. Regression analysis revealed a positive correlation between mast cells degranulation extent and the maximum value ofCa2+(i)(P < 0.01). Taken together, our present study suggested that UCN induced the increase of Ca2+(i) and degranulation of rat lung mast cells through CRF-R1. These findings may have implications for the pathophysiology of allergic and inflammatory lung disorders such as asthma, which is closely associated with mast cell activation and degranulation. Copyright (c) 2008 S. Karger AG, Basel.展开更多
文摘目的:探讨褪黑素(MLT)对足部电击所致创伤后应激障碍(PTSD)大鼠下丘脑-垂体-肾上腺(HPA)轴的影响。方法:利用足底电击法制备大鼠PTSD模型,通过腹腔注射方法给予治疗组大鼠MLT。通过拒俘反应测试检测大鼠的行为学变化,利用real time RT-PCR方法检测下丘脑中促肾上腺皮质激素释放激素(CRH)mRNA的表达,利用酶联免疫吸附试验(ELISA)检测血清中促肾上腺皮质激素(ACTH)、肾上腺素(EPI)和糖皮质激素(GC)的含量。结果:PTSD组大鼠拒俘反应明显(P<0.05),下丘脑中CRH mRNA表达升高(P<0.05),血清中ACTH和EPI明显升高(P<0.05),但是GC水平下降(P<0.05)。MLT治疗后可以明显缓解PTSD大鼠拒俘反应(P<0.05),同时降低下丘脑中CRH mRNA表达(P<0.05),降低血清中ACTH和EPI水平并升高GC的水平(P<0.05)。结论:MLT治疗可缓解PTSD大鼠的症状,并恢复HPA轴的神经内分泌平衡。
文摘Corticotropin-releasing factor(CRF), which activates the hypothalamic-pituitary-adrenal axis under stress, also has proinflammatory peripheral effects possibly through mast cells. The purpose of this study was to investigate the effect of urocortin (UCN), a 40-amino-acid CRF family peptide, on degranulation and intracellular calcium of rat lung mast cells. The activation and degranulation of mast cells were observed by Toluidine blue staining and transmission electron microscope. The intracellular calcium was investigated using confocal laser scanning microscopy and flow cytometry. The results indicated that all the three different concentrations of UCN(0.1, 1 and 10 mu M) significantly induced the activation and degranulation of rat lung mast cells in vitro. This effect was markedly blocked by selective CRF receptor 1(CRF-R1) antagonist antalarmin, but not by specific CRF receptor 2(CRF-R2) antagonist antisauvagine-30(anti-Svg-30). The results also showed that UCN caused a rapid peak increase inCa2+(i) at point of 300s after UCN treatment, followed by a decrease to a sustained plateau phase. The peak increase inCa2+(i) induced by UCN was significantly inhibited by antalarmin, but not by anti-Svg-30. This effect of UCN onCa2+(i) in rat lung mast cells was also found by flow cytometry. Regression analysis revealed a positive correlation between mast cells degranulation extent and the maximum value ofCa2+(i)(P < 0.01). Taken together, our present study suggested that UCN induced the increase of Ca2+(i) and degranulation of rat lung mast cells through CRF-R1. These findings may have implications for the pathophysiology of allergic and inflammatory lung disorders such as asthma, which is closely associated with mast cell activation and degranulation. Copyright (c) 2008 S. Karger AG, Basel.