Antigen-Induced Activation of Hypothalamic Cells (assessed by expression of the c-fos gene)

The aim of the present work was to study the activation of the expression of the c-fos gene (by in situ hybridization) in cells from rat (Sprague Dawley) hypothalamic structures 0.5, 2, 6, and 16 h after i.v. injections of tetanus toxoid (200 g/kg). Tetanus toxoid was selected as the antigen because it does not induce any general non-specific body reactions. Control animals received i.v. doses of apyrogenic physiological saline. The number of c-fos mRNA-positive cells in all the hypothalamic structures studied was insignificant 30 min after injections of tetanus toxoid. c-fos mRNA-positive cells were seen in the posterior, lateral, and anterior hypothalamic fields and in the dorsomedial and ventromedial hypothalamic nuclei 2 h after injections of tetanus toxoid. The intensity of c-fos mRNA expression decreased in the posterior, lateral, and anterior hypothalamic fields 6 h after injections of tetanus toxoid. The maximum number of c-fos mRNA-positive cells in the anterior field and the paraventricular nucleus of the hypothalamic induced by tetanus toxoid, as compared with reactions to administration of physiological saline, were seen at 6 h. Administration of tetanus toxoid and physiological saline did not active the synthesis of c-fos mRNA in the arcuate or supraoptic nuclei at any time point. The number of c-fos mRNA-positive cells returned to baseline by 16 h after tetanus toxoid injections. Thus, this study revealed the temporospatial pattern of activation of hypothalamic structures in response to exposure to an antigen.     

c-fos在CCK-8抗LPS所致的肺动脉平滑肌细胞损伤中的变化

目的:观察c-fos在八肽胆囊收缩素(CCK-8)减轻脂多糖(LPS)所致的肺动脉平滑肌细胞(PASMC)损伤中的变化。方法:贴块法培养大鼠PASMC。应用电镜技术和生化方法,观察细胞形态和测定细胞丙二醛(MDA)含量及乳酸脱氢酶(LDH)释放率;台盼蓝染色法记录PASMC蓝染率的变化;免疫细胞化学技术检测细胞内c-fos蛋白的表达情况。结果:CCK-8可减轻LPS引起的细胞超微结构损伤;CCK-8可降低LPS引起的细胞台盼蓝摄取率、MDA含量与LDH释放率的增高;LPS可轻微上调PASMC内c-fos蛋白表达,CCK-8可使该上调作用显著上升。结论:CCK-8可减轻LPS所致的PASMC损伤;CCK-8可能通过使c-fos蛋白表达上调来发挥其抗损伤作用。     

黄芪多糖调节创伤应激小鼠免疫功能的研究

目的采用小鼠截肢应激模型,探讨创伤应激状态下小鼠免疫功能变化及黄芪多糖对应激状态下机体免疫功能影响。方法将50只BALBc小鼠随机分为5组正常对照组(A),每天腹腔注射生理盐水0.5ml只;应激对照组(B),截肢后每天腹腔注射生理盐水0.5ml只;应激 APS高(C)、中(D)、低(E)剂量组,截肢后分别给予APS1000mgkg、500mgkg、250mgkg,生理盐水稀释至0.5ml腹腔注射,每天1次。连续注射3d后,采用免疫组织化学技术检测CD4 、CD8 、cfos蛋白表达,原位杂交检测NFκBmRNA、IL10mRNA表达,计算机图像分析系统定量。结果与A组比较,创伤后72hB组小鼠胸腺、脾脏组织中NFκBmRNA、IL10mRNA表达水平均明显升高(P<0.01);CD4 、CD4 CD8 比值显著减少(P<0.01);cfos抗原表达明显多于正常(P<0.01)。与B组比较,C、D、E组小鼠胸腺、脾脏组织中NFκBmRNA、IL10mRNA的表达受抑(P<0.01);胸腺、脾脏组织中CD4 抗原水平、CD4 CD8 比值升高(P<0.01);胸腺、脾脏组织中cfos抗原水平降低(P<0.01)。与A组比较,C组胸腺、脾脏组织中NFκBmRNA、IL10mRNA的表达,CD4 抗原、CD8 抗原、cfos抗原分布差异无显著性(P>0.05)。结论创伤后小鼠细胞免疫功能明显紊乱;而黄芪多糖体内应用可有效恢复其免疫功能。     

自发性脑卒中诱导原癌基因c－fos在大鼠脑内的表达

用免疫组织化学（ＡＢＣ）方法，对易卒中型肾血管性高血压大鼠高血压晚期自发形成脑卒中时以及高血压早期和中期脑内ｃ－ｆｏｓ原癌基因蛋白（ＦＯＳ）的表达进行了观察．在高血压晚期，假手术组不出现脑卒中，但个别大鼠的扣带皮质和梨状皮质出现微弱的ＦＯＳ表达；手术组都出现脑卒中，其中３例脑内未见ＦＯＳ表达，４例则于大脑皮质、海马、黑质和下丘脑等处出现程度不等的ＦＯＳ表达．高血压早期，手术组和假手术组的下丘脑、隔核、中脑中央灰质和丘脑室旁核出现分布状态和强弱都相似的ＦＯＳ表达．高血压中期，手术组和假手术组脑内未见ＦＯＳ表达．本研究结果提示：（１）高血压晚期，自发性脑卒中能诱导ｃ－ｆｏｓ在脑内的广泛表达，脑内不同部位ＦＯＳ表达的机制和功能意义不同，本文对其进行了讨论；（２）腹部手术能诱导下丘脑等与内脏功能调节有关的功能区ＦＯＳ的表达；（３）高血压早期和中期，通过ｃ－ｆｏｓ表达的方法未能发现高血压对大鼠脑功能活动的影响。     

食管内脏高敏感性动物模型的建立和评价

目的建立食管内脏高敏感性动物模型。方法采用腹腔注射鸡卵清蛋白（OVA）基础致敏联合食管酸灌注的方法处理SD大鼠，并采用免疫组织化学方法和显微图像分析技术评价内脏高敏感性一食管化学刺激大鼠模型的可靠性。结果OVA基础致敏联合食管酸灌注组大鼠被激活了一个复杂而广泛的大脑网络，其在额顶皮质、岛叶、扣带皮质、中央杏仁核、Kfilliker-Fuse核、疑核、臂旁核、下丘脑室旁核、丘脑室旁核、三叉旁核、孤束核、最后区、延髓网状核等Fos样免疫活性（FLI）神经元的数目均显著高于其余各组（P〈0．05）。模型组大鼠在中央杏仁核、臂旁核、室旁核、三叉旁核、孤束核的FLI阳性产物的平均光密度（OD）值亦较其余各组明显增高（P〈0．05）。结论预先腹腔注射鸡卵清蛋白基础致敏联合食管酸灌注可成功建立食管内脏高敏感性动物模型。     

电针调控大鼠胃运动中c-fos表达及其意义

目的 原癌基因c-fos可以作为神经元被激活的一种标志,以原癌基因c-fos的表达为观察指标。结合胃电的变化来探讨穴位电针调节胃运动功能的作用机制。方法 采用免疫组织化学方法及电生理的方法,观察电针刺激足三里等不同穴位,c-fos在中枢延髓孤束核（NTS）及迷走神经背运动核（DMV）中的表达,同时采用浆膜法检测胃电变化情况。结果 电针刺激足三时等不同穴位c-fos在NTS及DMV中的表达情况不同,且胃电也发生较为明显的变化,结论 穴位电针对胃运动具有调节作用。以c-fos的表达作为激活标志,提示这种调节作用可能是通过对NTS及DMV神经元的激活而实现的。     

硫代修饰c-fos反义寡脱氧核苷酸的潜在抗焦虑作用研究

目的 :探讨硫代修饰c fos反义寡脱氧核苷酸的潜在药理学价值及分子机制。方法 :建立焦虑的动物模型 ,将硫代修饰c fos反义寡脱氧核苷酸注入大鼠侧脑室 ;高架十字迷宫和空场实验评估大鼠焦虑行为 ,免疫组织化学技术检测Fos蛋白表达 ,计算机图像分析系统定量。结果 :c fos反义寡核苷酸减少了下丘脑室旁核部位的Fos免疫反应阳性神经元 ,抑制率 5 7.0 3%。并可以拮抗应激所至的焦虑相关行为 ,与diazepam效果类似而不影响中枢神经系统兴奋性。结论 :提示c fos是焦虑形成机制中不可或缺的环节 ,c fos硫代修饰反义寡核苷酸具有潜在的抗焦虑作用     

心室成纤维细胞条件培养液促进成纤维细胞增殖

目的：探讨心室成纤维细胞条件培养液成纤维细胞自身增殖作用。方法：利用成纤维细胞培养、同位素掺入率测定和RT－PCR方法。结果：心室成纤维细胞条件培养液能显增加细胞自身的[^3H]-胸腺嘧啶核苷的掺入率,并具有剂量依赖性,促进细胞自身的c-fos基因的表达,刺激后1h达高峰。ETA受体拮抗剂BQ123能部分阻断条件培养液增加成纤维细胞增殖的作用,而AT1受体拮抗剂CV11974和（α-肾上腺素受体拮抗剂regitin无此效果。结论：心室成纤维细胞能自分泌内皮素等生物活性物质,促进成纤维细胞增殖。     

Blockade of neurotensin receptors suppresses the dopamine D1/D2 synergism on immediate early gene expression in the rat brain

A remarkable feature of dopamine functioning is that the concomitant activation of D1-like and D2-like receptors acts to intensify the expression of various dopamine-dependent effects, in particular the expression of the immediate-early genes, c-fos and zif268. Using non-peptide neurotensin receptor antagonists, including SR48692, we have determined that blockade of neurotensin receptors reduced the cooperative responses of direct acting D2-like (quinpirole) and partial D1-like (SKF38393) dopamine agonists on the expression of Fos-like antigens and zif268 mRNA. Pretreatment with SR48692 (3 and 10 mg/kg) reduced the number of Fos-like immunoreactive cells produced by the combined administration of SKF38393 (20 mg/kg) and quinpirole (1 mg/kg) in the caudate-putamen, nucleus accumbens, globus pallidus and ventral pallidum. High-affinity neurotensin receptors are likely to be involved in these D1-like/D2-like cooperative responses, as compounds structurally related to SR48692, SR48527 (3 mg/kg) and its (-)antipode, SR49711 (3 mg/kg), exerted a stereospecific antagonism in all selected brain regions. Pretreatment with SR48692 (10 mg/kg) also diminished Fos induction by the indirect dopamine agonist, cocaine (25 mg/kg), particularly at the rostral level of the caudate-putamen. In situ hybridization experiments in the caudate-putamen indicated that SR48692 (10 mg/kg) markedly reduced zif268 mRNA labelling produced by SKF38393 plus quinpirole in cells not expressing enkephalin mRNA, but was unable to affect the concomitant decrease of zif268 mRNA labelling in enkephalin-positive cells. Taken together, the results of the present study indicate that neurotensin is a key element for the occurrence of cooperative responses of D2-like and partial D1-like agonists on immediate-early gene expression.