慢性束缚应激大鼠海马脑啡肽mRNA和前强啡肽mRNA 表达及中药复方的影响

目的:研究慢性束缚应激时大鼠海马脑啡肽和前强啡肽mRNA基因表达的变化以及逍遥散、四君子汤、金匮肾气丸三种中药复方对其的影响.方法:用特制束缚架连续束缚7 d与21 d,每天3 h的方法制作大鼠束缚应激模型;以RT-PCR反应,扩增脑啡肽和前强啡肽基因,同时以β-actin作为内对照,用凝胶图像分析系统进行扫描并分析,把目的基因的光密度与内参照条带的光密度进行比较后进行半定量分析.结果:7 d模型组大鼠海马前强啡肽mRNA的表达明显增强(P＜0.01),21 d模型组海马脑啡呔mRNA和前强啡肽mRNA的表达明显增强(P＜0.01);三个复方均能降低海马内前强啡肽mRNA的表达(P＜0.01),逍遥散和四君子汤能降低脑啡呔mRNA的表达(P＜0.01).结论:逍遥散对脑啡呔mRNA前强啡肽mRNA的基因表达的改善作用明显优于金匮肾气丸组.     

逍遥散对慢性束缚应激模型大鼠相关脑区CRF基因表达的影响

目的:观察慢性束缚应激大鼠相关脑区CRF mRNA(下丘脑、垂体、海马、皮层)含量变化以及逍遥散对其影响.方法:用RT-PCR和图像分析方法测定相关脑区CRF mRNA含量变化.结果:应激组较正常对照组在下丘脑CRF-1基因表达下调(P<0.01).在下丘脑逍遥散组较应激组CRF-1基因表达显著下调(P<0.01),CRF-2基因表达显著上调(P<0.01);在海马区逍遥散组CRF-2基因表达较模型组上调(P<0.05);在皮层逍遥散组CRF-1基因表达较应激组则显著上调(P<0.01).结论:逍遥散组对慢性束缚应激中枢神经肽CRF的调节位点在下丘脑、垂体、海马和皮层,充分证实逍遥散的调节靶点与下丘脑、边缘系统及皮层中枢有关.     

长期运动应激对人白细胞糖皮质激素受体的影响

自从Selye提出全身适应症的学说以来的半个多世纪,有关应激的研究已相当广泛和深入。生理性和病理性应激时,肾上腺糖皮质激素(GC)分泌增多已众所周知。但要全面认识应激时的GC效应,还必须研究应激时靶细胞对GC的反应,而糖皮质激素受体(GR)是靶细胞对GC反应的决定性因素。已有不少报道表明,急性的生理、病理性应激时,GR减少,但有关慢性应激时GR的变化,迄今未见报道。我们以长期经历运动应激的专业运动员为对象,研究了慢性应激对GR的影响。     

不同时程束缚水浸应激对大鼠胃排空的影响

目的研究不同时程慢性束缚水浸应激对大鼠胃排空的影响。方法48只雄性150 g左右SD大鼠被随机分为6组,即实验3、72、8 d组和对照3、72、8 d组,每组8只。实验期间,每日观察大鼠体重、一般状况及行为学指标。实验组23℃水域箱内束缚水浸1 h/d,对照组自由摄食饮水。采用半固体排空实验（阿拉伯胶炭糊）来检测胃排空率,数据录入SPSS 13.0进行分析处理。结果①体重增加情况：不同组别和不同应激时间这两个因素对体重增加的影响差异均有显著性。②胃排空率：对照各组间比较均无统计学差异。3 d组间（实验3d组与对照3 d组）大鼠胃排空率无差异;而7 d组间和28 d组间比较则明显异常。随着应激时间的延长,实验组胃排空率呈现了先增高（7 d时）后降低（28 d）的变化趋势,且实验3 d组与7 d组、7 d组与28 d组间比较均有明显的统计学意义,而3 d组与28 d组比较则无统计学差异。结论不同时程的慢性束缚水浸应激可以导致大鼠胃排空率改变;随着应激时间的延长,呈现先上升后下降的规律。     

糖皮质激素受体的研究进展

糖皮质激素受体(glucocorticoid receptor,GR)在机体的生命活动中具有重要作用.它是激素核受体家族中的一个主要成员,同时也是一种重要的核转录因子,转录调控多种基因表达.糖皮质激素作用的发挥必须与糖皮质激素受体结合.糖皮质激素受体不仅能参与机体应激反应,而且具有抗炎抗免疫作用和促细胞凋亡作用.目前已知的GR有三种类型,分别为α、β和P型,糖皮质激素受体在应激及GC抵抗中扮演着重要的角色.     

AMPA受体和相关蛋白在束缚应激大鼠相关脑区的表达变化及逍遥散对其影响

目的：观察海马及杏仁核α-氨基羟甲基恶唑丙酸（AMPA）受体亚基和相关调节蛋白在束缚应激状态下蛋白表达变化及逍遥散的调节作用。方法：使用每天捆绑3 h的方法制作慢性束缚应激动物模型,并用逍遥散进行干预,分别于7 d后和21 d后用Western blot方法检测各组大鼠海马CA1区、CA3区、齿状回（DG）和杏仁核的AMPA受体亚基GluR2/3及N-乙基顺丁烯二酰亚胺敏感性的融合蛋白（NSF）、PKC作用蛋白1（PICK1）蛋白表达的情况。结果：7 d应激可使DG和杏仁核的GluR2/3、NSF表达显著降低（P均〈0.05）,使PICK1在CA1区的表达量显著增多（P〈0.05）,逍遥散对PICK1变化显示出一定调节作用。21 d应激可使CA1区的GluR2/3、NSF表达升高,其中GluR2/3有显著性差异（P〈0.01）,而在杏仁核表达有降低趋势,逍遥散对其均有显著调节作用（均为P〈0.05）,21 d应激使杏仁核PICK1表达量出现升高趋势,逍遥散可显著降低其表达（P〈0.05）。结论：AMPA受体在短期重复应激和慢性应激状态下反应不同,海马和杏仁核反应相反,逍遥散对慢性应激状态下AMPA受体表达的调节作用较短期重复应激强。     

疏肝、健脾、补肾复方对慢性束缚应激大鼠行为学和免疫功能的影响

目的　研究慢性束缚应激时大鼠行为学和免疫功能的变化以及疏肝、健脾、补肾三种中药复方对其影响。方法　用特制束缚架连续束缚 2 1d(或 7d) ,每天 3h的方法制作大鼠束缚应激模型 ,观察大鼠行为学和免疫功能的变化。结果　慢性束缚应激后 ,大鼠的行为学发生了明显的变化 ,血清IL - 1β 上升 ,IL - 2和IL - 6下降 ,并且随着束缚时间的延长变化越明显。结论　逍遥散、四君子汤和金匮肾气丸能改善大鼠行为学的变化 ,明显增强慢性束缚应激大鼠的免疫功能。     

慢性应激不同方式对大鼠血清皮质酮的影响

目的：比较慢性应激不同方式对生理状态大鼠血清皮质酮水平的影响,研究机体慢性应激反应的整体性适应特征。方法：采用连续4周的适宜游泳、束缚和二者复合的三种应激方式后,测定大鼠血清皮质酮基础含量,分析不同慢性应激方式对皮质酮水平的影响。结果：血清皮质酮水平与对照组比较,复合组无显著性差异;游泳组虽升高但无显著性;束缚组升高有显著性意义。结论：束缚可致大鼠血清皮质酮水平增高;初步认定游泳与束缚复合慢性应激方式可能对机体的整体适应性能具有积极意义。     

杏仁核SIRT1对慢性束缚应激大鼠抑郁样行为的影响

目的:观察杏仁核沉默信息调节因子1(SIRT1)蛋白对慢性束缚应激(CRS)大鼠抑郁样行为的影响。方法:60只SD雄性大鼠随机分为6组(n=10):正常对照组(Control)、慢性束缚应激组(CRS)、CRS+氟西汀(FLU)组(CRS+FLU)、CRS+生理盐水组(CRS+NaCl)、CRS+SIRT1过表达组(CRS+AAV-SIRT1)和CRS+空载体组(CRS+AAV-EGFP)。除了正常对照组,其余各组均接受慢性束缚应激造模21 d。造模结束后,氟西汀组和生理盐水组大鼠每天分别灌胃给予氟西汀(10 mg/kg)或生理盐水(10 mg/kg),持续3周;SIRT1过表达组和空载体组大鼠分别脑立体定位,注射腺相关病毒AAV-SIRT1或AAV-EGFP于杏仁核,待病毒表达3周;正常组和抑郁症组大鼠则不给予任何药物。应用糖水偏好实验(SPT)、旷场实验(OFT)和强迫游泳实验(FST)检测各组大鼠的抑郁样行为学变化;蛋白免疫印迹实验检测大鼠杏仁核中SIRT1蛋白的表达;免疫荧光技术检测大鼠杏仁核中SIRT1阳性细胞数量。结果:与正常对照组相比,CRS抑郁大鼠杏仁核中SIRT1蛋白...     

脊椎动物脑发育中糖皮质激素受体功能的研究进展

糖皮质激素受体（glucocorticoid reccptor,GR）广泛分布在脊椎动物中枢神经系统的多个组织区域中,而且结构及功能保守。在与激素结合的状态下,受体能够特异性地与靶基因的启动子结合影响基因的表达,或通过激活G蛋白偶联的信号途径引起神经递质的释放。外界环境刺激和外源糖皮质激素暴露都能改变GR在脑中的表达,并对神经的发育及功能产生影响,同时也对学习、记忆以及情感等高级神经活动和行为起到重要的作用。该文对脊椎动物糖皮质激素受体的结构和在脑中的分布,以及对神经发育和功能的影响及其中的分子机制的最新研究进展进行综述。     

Immunocytochemical study of the glucocorticoid receptor in rat liver nuclei after hyperthermic stress

The presence of glucocorticoid receptors (GR) in rat liver nuclei over a 24 h time period following hyperthermic stress at 41 degrees C was immunocytologically studied using unfixed nuclear smears. Liver nuclei in unstressed animals were found to be immunonegative for GR. However, intense GR immunopositivity followed by a subsequent gradual decrease in receptor levels was observed in the nuclei of test animals during the first 2 h after stress. This stress-related increase in the receptor nuclear level was greater than the increase seen after dexamethasone administration. These results suggest that hyperthermic stress could potentiate the hormonal stimulation of receptor nuclear translocation.     

Role of TrkB expression in rat adrenal gland during acute immobilization stress

Expression of tyrosine receptor kinase B (TrkB), a receptor for brain‐derived neurotrophic factor (BDNF), is markedly elevated in the adrenal medulla during immobilization stress. Catecholamine release was confirmed in vitro by stimulating chromaffin cells with recombinant BDNF. We investigated the role of TrkB and the localization of BDNF in the adrenal gland during immobilization stress for 60 min. Blood catecholamine levels increased after stimulation with TrkB expressed in the adrenal medulla during 60‐min stress; however, blood catecholamine levels did not increase in adrenalectomized rats. Furthermore, expression of BDNF mRNA and protein was detected in the adrenal medulla during 60‐min stress. Similarly, in rats undergoing sympathetic nerve block with propranolol, BDNF mRNA and protein were detected in the adrenal medulla during 60‐min stress. These results suggest that signal transduction of TrkB in the adrenal medulla evokes catecholamine release. In addition, catecholamine release was evoked by both the hypothalamic–pituitary–adrenal axis and autocrine signaling by BDNF in the adrenal gland. BDNF–TrkB interaction may play a role in a positive feedback loop in the adrenal medulla during immobilization stress.     

Frequent promoter hypermethylation and expression reduction of the glucocorticoid receptor gene in breast tumors

Previous studies have found that expression of the Glucocorticoid Receptor (GR) is altered or reduced in various cancers, while the GR promoter has been shown to be methylated in gastric, lung, and colorectal cancers. Examining a small cohort of matched normal and breast cancer samples we found that GR levels were dramatically reduced in almost all tumors in relation to their normal tissue. The methylation status of the GR promoter was assessed to determine if this observed decrease of expression in breast tumors could be due to epigenetic regulation. While it was not methylated in normal tissue, the GR proximal promoter was methylated in 15% of tumor samples, particularly, but not exclusively, in Estrogen Receptor positive tumors. GR expression in these tumors was particularly low and loss of GR expression was specifically correlated with methylation of the proximal promoter GR B region. Overall, these results show that hypermethylation of the promoter in tumors is a frequent event and suggests that GR may act as a tumor suppressor in breast tissue.     

Frequent promoter hypermethylation and expression reduction of the glucocorticoid receptor gene in breast tumors

Previous studies have found that expression of the Glucocorticoid Receptor (GR) is altered or reduced in various cancers, while the GR promoter has been shown to be methylated in gastric, lung, and colorectal cancers. Examining a small cohort of matched normal and breast cancer samples we found that GR levels were dramatically reduced in almost all tumors in relation to their normal tissue. The methylation status of the GR promoter was assessed to determine if this observed decrease of expression in breast tumors could be due to epigenetic regulation. While it was not methylated in normal tissue, the GR proximal promoter was methylated in 15% of tumor samples, particularly, but not exclusively, in Estrogen Receptor positive tumors. GR expression in these tumors was particularly low and loss of GR expression was specifically correlated with methylation of the proximal promoter GR B region. Overall, these results show that hypermethylation of the promoter in tumors is a frequent event and suggests that GR may act as a tumor suppressor in breast tissue.     

重复制动应激对雌性大鼠下丘脑-垂体-卵巢轴的影响

目的: 探索重复制动应激对雌性大鼠下丘脑-垂体-卵巢轴的影响。方法: 40只SD雌鼠随机分为两组(n=20),对照组和实验组,一组正常饲养,一组采取递增负荷束缚应激,每天置于束缚器内制动应激一次(从上午9:00开始),第1日制动2 h,以后采用递增负荷,每日增加0.5 h,持续两周,通过检测体重、脏器系数、动情周期、性激素、病理和相关基因的表达探索其对下丘脑-垂体-卵巢轴的危害。结果: 重复制动应激使雌性大鼠体重下降、动情周期延长,卵巢和子宫的脏器系数和形态发生改变,利用qPCR技术对其相关基因检测,发现下丘脑促性腺激素释放激素、垂体促性腺激素释放激素受体、促卵泡生成素和促黄体生成素mRNA的表达显著下降,卵巢促卵泡生成素和黄体生成素受体 mRNA的表达显著上升,卵巢和子宫雌激素受体mRNA的表达显著下降。结论: 重复制动应激可能通过干扰下丘脑-垂体-卵巢轴的内分泌调节作用,使动情周期紊乱,从而损伤雌性动物的性腺和生殖内分泌功能。     

Effects of Baihe Dihuang powder on chronic stress depression rat models

Purpose

Explore the effect of Baihe Dihuang powder on chronic stress depression rat models.