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正常人和小鼠骨髓细胞体外平皿液体培养中形成的贴壁细胞层,具有骨髓基质成分和功能,在此贴壁细胞层或基质层上,培养粒系祖细胞 CFU-C(Colony Forming Unit-Culture),以不带基质层的 CFU-C 为对照(100%)。结果第一周基质层上 CFU-C 为对照51.07±3.54%(人)和27.30±4.68%(鼠);第二周者则与对照相近;笫三周之 CFU-C 则上升达150.70±17.63%(人)与146.89±10.01%(鼠)。示基质层对 CFU-C 的增殖分化,在1~3周呈先抑制后刺激的效应。并观察了10例用山莨菪碱治疗的再生障碍性贫血患者之骨髓三周基质层,对正常骨髓CFU-C 影响。治疗前4例,基质层上 CFU-C 较对照<80%,示有抑制作用。此4例均治疗有效。其中2例复查,抑制作用消失。其余6例,其基质层上 CFU-C,均较对照>80%,仅1例用山莨菪碱治疗有效。这种基质层上培养 CFU-C 的方法,可用于实验或临床,研究骨髓基质支持造血的功能。  相似文献   

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磷脂酶A2、环氧合酶以及前列腺素E合成酶是前列腺素E合成途径中顺序起作用的重要酶类,其中前列腺素E合成酶有两种不同的亚型,分别介导不同的前列腺素E合成反应。前列腺素E可与其受体特异性结合,并通过旁分泌和自分泌两种形式调节细胞反应,参与多种生理过程。近来研究发现,前列腺素E受体不仅存于质膜,而在核膜上也大量存在。前列腺素E核受体介导的信号转导途径与膜受体介导的信号途径不同,对于基因转录的调控机制也不同。本文综述并探讨了上述分子所组成的网络系统在哺乳动物生殖,尤其是雌性生殖过程中所发挥的重要作用。  相似文献   

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本文采用半固体单层琼脂培养和液体培养_3H-TdR掺入法观察PGE_2对小鼠骨髓CFU-GM增殖分化的影响,实验结果表明PGE_2可明显抑制CFU-GM增殖和分化,抑制率与PGE_2剂量呈负相关。其50%抑制率所对应的PGE_2剂量,琼脂培养法为4.8×10~(-8)mol/L, ~3H-TdR掺入法为3.5×10~(-8)mol/L,两种方法观察的结果相近。压片染色集落分类的结果还表明PGE_2对CFU-GM各类型集落形成均有明显的抑制作用。其中以CFU-M和CFU-GM抑制最为明显。1×10~(-8)—1.2×10~(-8)mol/L的PGE_2浓度就可抑制CFU-M和CFU-GM增殖50%,当PGE_2浓度增至7.3×10~(-8)mol/L时CFU-M增殖即被抑制90%,说明单核-巨噬系祖细胞对PGE_2是十分敏感的。PGE_2对粒系集落的抑制作用机理尚不清楚。  相似文献   

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Yang HW 《生理科学进展》2009,40(4):317-320
环氧合酶-2 (cyclooxygenase-2,COX-2)是催化花生四烯酸转化为前列腺素的限速酶,广泛参与脑创伤、缺血诱导的神经元损伤、炎症反应及神经变性性疾病等.COX-2在神经病理学中的作用与神经元的突触变化有关.增强或抑制COX-2表达可增强或抑制兴奋性谷氨酸能神经元的神经传递和长时程增强 (LTP),这些效应由COX-2的主要产物前列腺素E2(PGE2)及其受体亚型EP2所介导.因此,阐明COX-2在突触信号中的作用机制将有助于设计新的药物来预防、治疗及减轻神经源性炎症相关的神经紊乱性疾病.  相似文献   

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前列腺素E_1对大鼠离体胃平滑肌运动的作用瞿颂义,李伟,郑天珍(兰州医学院生理学教研室兰州730000)胃平滑肌细胞合成的多种前列腺素(PG)调节着胃的运动,能使固体食物的排空减慢、液体食物的排空加快。为此我们取大鼠胃各部位的平滑肌条,观察其对PGE...  相似文献   

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前列腺素E2对免疫细胞及炎症相关疾病的调控作用   总被引:1,自引:0,他引:1  
前列腺素E2(prostaglandin E2,PGE2)是一种极其重要的脂质代谢产物,在受到生理或病理的各种刺激,尤其是有害刺激时被释放,在发热、炎症和血压调节中均发挥着重要作用.PGE2通过4种功能相互拮抗的的受体(E-prostanoid receptors,EP1、EP2、EP3和EP4)而广泛参与机体及细胞代谢过程.一直以来,人们都认为前列腺素在免疫过程中发挥的作用相当有限,部分原因是因为抑制类前列腺素合成的非甾体类抗炎药在机体免疫过程中没有发挥明显作用.但近来的研究表明,PGE2很可能在免疫细胞的发育分化及免疫应答过程中也起重要作用.本文主要对前列腺素与免疫系统的关系进行分析和总结,并重点讨论相关研究的新近进展.  相似文献   

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前列腺素E2(prostaglandin E2,PGE2)是由花生四烯酸经环氧合酶途径代谢生成的前列腺素之一,PGE2通过其4种受体亚型(EP1、EP2、EP3和EP4)介导产生多种生理功能,同时是缺血性脑损伤中的重要炎症介质.而在缺血性脑卒中发病机制中,PGE2激活不同受体亚型而发挥不同的作用.本文将从受体作用特点的...  相似文献   

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骨髓基质干细胞向心肌样细胞分化的实验研究   总被引:2,自引:0,他引:2  
目的探讨大鼠骨髓基质干细胞向心肌样细胞分化后超微结构和细胞因子表达的变化,为下一步细胞移植治疗扩张型心肌病提供理论依据。方法在体外扩增、定向诱导骨髓基质干细胞向心肌样细胞分化的基础上,电镜下观察骨髓基质干细胞诱导前后超微结构的改变,RT-PCR检测心肌特异性因子ANP、BNP、α-MHC、β-MHC的表达,并与原代培养的心肌细胞比较,观察二者之间的生物学异同。结果免疫组化法证实诱导后的骨髓基质干细胞向心肌样细胞分化,电镜下胞浆内可见糖原颗粒,肌原纤维排列与原代培养的心肌细胞相似;RT-PCR证实诱导后的骨髓基质干细胞表达心肌特异性因子ANP、BNP、α-MHC、β-MHC。结论骨髓基质干细胞经5-氮胞苷定向诱导后在超微结构和细胞因子的表达上类似于心肌细胞,已向心肌样细胞分化。  相似文献   

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REGULATION OF HUMAN MYELOPOIESIS BY PROSTAGLANDIN E AND LACTOFERRIN   总被引:3,自引:0,他引:3  
Studies on human myeloid stem cell proliferation indicate that progenitor cell populations committed to monocytoid differentiation are preferentially inhibited by prostaglandin E (PGE). the addition of PGE but not PGF to day 7 CFUGM cultures upon initiation results in the dose-dependent inhibition of total colony and cluster formation. Morpholigical analysis of proliferating clones demonstrates that the effect of PGE on total colony and cluster formation results from the selective inhibition of monocyte-macrophage colony forming cells. Mixed monocytoid/neutrophil colony formation was markedly less sensitive and neutrophil and eosinophil colony formation essentially insensitive to the inhibitory effects of PGE. the inhibition of monocytoid colony formation by PGE1 extends equally well to day 13 CFUGM, but not to CFUGM in suspension culture. the observed effects of PGE1 on monocytoid committed pre-CFUGM and day 7 and day 14 CFUGM indicate that sensitivity to inhibition by PGE increases with progenitor cell maturity. Specificity analysis indicates that prostaglandins of the E series (PGE1, PGE2) are by far the most active naturally occurring prostanoate compounds inhibiting CFUGM proliferation. The addition of iron saturated lactoferrin to liquid cultures of human peripheral blood monocytes, inclusion into mononuclear cell feeder layers or addition to agar cultures proliferating in response to endogenously produced CSFs, results in the equivalent inhibition of CSFs necessary for day 7 and day 14 monocytoid and/or neutrophil and eosinophil colony and cluster formation. These results indicate roles for PGE and lactoferrin in myeloid stem cell regulation in vitro and suggest that they may serve as physiological regulators of granulocyte and monocyte proliferation.  相似文献   

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目的研究足月妊娠子宫平滑肌与蜕膜组织中前列腺素E2(Prostaglandin E2,PGE2)的浓度、子宫平滑肌中PGE2受体-2(PGE2 recepor-2,PGER2)蛋白的表达与缩宫素引产成功率的关系。方法选择缩宫素引产成功与缩宫素引产失败的孕妇,于剖宫产术中取子宫平滑肌及子宫蜕膜组织。分别行ELISA法检测组织匀浆中PTGE2的浓度,Western blot检测子宫平滑肌中PTGER2蛋白的表达。结果缩宫素引产成功组比缩宫素引产失败组子宫平滑肌、子宫蜕膜组织中PTGE2浓度显著增高(P〈0.01);缩宫索引产成功组比缩宫素引产失败组子宫平滑肌组织中PTGER2蛋白的表达也明显增高(P〈0.01)。结论子宫平滑肌与蜕膜组织中PTGE2浓度、子宫平滑肌组织中PTGER2蛋白的表达量与缩宫素引产成功率关系密切。  相似文献   

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本文报道了重组白介素6-假单胞菌外毒素融合蛋白(IL-6-PE40)对正常BN大鼠骨髓粒系造血的体外效应。10ng/ml的IL-6-PE40对高表达IL-6受体的U266骨髓瘤细胞的蛋白质合成抑制率为50%,1000ng/ml则为100%。1~1000ng/mlIL-6-PE40对正常骨髓未纯化细胞的CFU-GM集落形成和DNA合成无明显抑制,但IL-6却具有一定的刺激效应。提示正常骨髓粒系祖细胞和骨髓细胞可能不表达IL-6受体,IL-6-PE40对粒系造血仍具有某些细胞毒作用,但被IL-6-PE40中的IL-6极大地削弱了。  相似文献   

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FAP在乳腺癌间质中的表达及其与微血管密度的关系   总被引:3,自引:0,他引:3  
目的观察乳腺各组良恶性病变中FAP表达变化及其与微血管密度(MVD)的关系。方法本文应用免疫组织化学,Western Blotting实验方法观察FAP在乳腺腺病、乳腺纤维腺瘤、乳腺非浸润癌(导管原位癌),乳腺浸润性导管癌及MCF-7-CCC-HPF-1、MDA-MB-231-CCC-HPF-1共培养模型中的表达变化并探讨FAP与微血管密度(MVD)的关系。结果FAP在乳腺腺病、乳腺纤维腺瘤间质中表达阴性,在乳腺非浸润癌(导管原位癌)、乳腺浸润性导管癌间质中高表达;FAP在细胞系MDA-MB-231中不表达,在共培养模型MCF-7-CCC-HPF-1,MDA-MB-231-CCC-HPF-1中均有表达;FAP表达与MVD相关(P<0.05)。结论FAP可能作为判定乳腺良恶性病变的指标之一,且可能在促进乳腺癌浸润、生长及转移中发挥一定作用。  相似文献   

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Cellular differentiation is controlled by a variety of factors including gene methylation, which represses particular genes as cell fate is determined. The incorporation of 5-azacytidine (5azaC) into DNA in vitro prevents methylation and thus can alter cellular differentiation pathways. Human bone marrow fibroblasts and MG63 cells treated with 5azaC were used as models of osteogenic progenitors and of a more mature osteoblast phenotype, respectively. The capacity for differentiation of these cells following treatment with glucocorticoids was investigated. 5azaC treatment led to significant expression of the osteoblastic marker alkaline phosphatase in MG63 osteosarcoma cells, which was further augmented by glucocorticoids; however, in human marrow fibroblasts alkaline phosphatase activity was only observed in glucocorticoid-treated cultures. MG63 cells represent a phenotype late in the osteogenic lineage in which demethylation is sufficient to induce alkaline phosphatase activity. Marrow fibroblasts are at an earlier stage of differentiation and require stimulation with glucocorticoids. In contrast, the expression of osteocalcin, an osteoblastic marker, was unaffected by 5azaC treatment, suggesting that regulation of expression of the osteocalcin gene does not involve methylation. These models provide novel approaches to the study of the control of differentiation in the marrow fibroblastic system.  相似文献   

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The effects of EDTA·Mg or GEDTA·Mg on the uptakeof nutrient ions, the release of Ca++ and nucleotides into themedium and the nucleic acid contents in rice and red bean rootswere investigated.
  1. Both EDTA and EDTA·Mg induced similarly the release ofCa from roots.
  2. EDTA·Mg as well as EDTA brought abouta significant repressionin K uptake, but had an insignificantor no effect on P, NH4and NO3 uptakes. EDTA·Ca did notrepress K, P, NH4 andNO3 uptakes.
  3. EDTA or GEDTA acceleratedthe degradation of nucleic acid andthe release of nucleotides,while EDTA·Mg or GEDTA·Mghad no such effect.
These results indicate that the indispensable role of intracellularCa in K uptake does not appear to be directly associated withRNA metabolism. (Received July 29, 1965; )  相似文献   

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Mammalian erythropoiesis, as assayed by erythroid colony formation in vitro, is enhanced by cyclic adenosine nucleotides and agents which are capable of raising intracellular cyclic AMP (cAMP) levels. With canine marrow cells as target, this enhancement was shown to be specific for cAMP and its mono- and dibutyryl derivatives. Adenosine and its derivatives, such as AMP, ADP and ATP, and other cyclic nucleotides, such as cGMP, dibutyryl-cGMP, cCMP and cIMP and sodium butyrate were inactive. The phosphodiesterase inhibitor, RO-20-1724, and the adenyl cyclase stimulator, cholera enterotoxin, both markedly increased colony numbers. Studies with tritiated thymidine showed that about 50% of the cells responding to either erythropoietin (ESF) or dibutyryl cAMP (db-cAMP) were in DNA synthesis. However, by unit gravity sedimentation velocity analysis, the peak of ESF-responsive colony forming cells sedimented more rapidly (8.7 ± 0.2 mm/hr) than the peak of db-cAMP-responsive cells (7.5 ± 0 mm/hr). These results demonstrate that adenyl cyclase-linked mechanisms influence in vitro erythropoietic proliferation and suggest that other hormones and simple molecules might interact with surface receptors and thus modulate the action of ESF at the cellular level.  相似文献   

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