缺氧性肺动脉高压大鼠肺组织中血小板源性生长因子和c—my…

本研究分析了大鼠肺组织中血小板源性生长因子Ａ链、Ｂ链和ｃ－ｍｙｃ原癌基因ｍＲＮＡ。正常肺组织可表达１．７ｋｂ的ＰＤＧＦ－ＡｍＲＮＡ和３．５ｋｂ的ＰＤＧＦ－ＢｍＲＮＡ,还有少量２．２ｋｂｃｍＲＮＡ．在缺氧过程中,ＰＤＧＦ－Ｂ链ｍＲＮＡ和ｃ－ｍｙｃｍＲＮＡ迅速增加,至缺氧１４ｄ时,分别为正常的３倍和５倍。而ＰＤＧＦ－ＡｍＲＮＡ在缺氧７ｄ时增高,而后又略有降低。结果表明：缺氧的肺组织局生成的ＰＤＧＦ激活     

缺氧对大鼠肺组织肺血管sis原癌基因和PDGF-BB蛋白表达的影响

为了探讨血小板生长因子ＢＢ（ＰＤＧＦ－ＢＢ）在缺氧性肺血管结构重塑中作用,通过建立大鼠缺氧性肺血管重塑动物模型,运用原位杂交技术和免疫组织化学染色技术检测不同缺氧时期大鼠肺组织中原癌基因ｓｉｓｍＲＮＡ和ＰＤＧＦ－ＢＢ蛋白表达。结果：（１）随着缺氧时间的延长,肺动脉壁肌层增厚,管腔变窄;（２）正常对照组肺组织及肺血管壁ｃ－ｓｉｓｍＲＮＡ和ＰＤＧＦ－ＢＢ蛋白质均极少表达（＋）;（３）缺氧３天后,两者表达均增多（）;（４）缺氧７天后其表达达高峰并持续至１４天（～）;（５）缺氧２１天后,两者表达均降低,但仍高于正常对照组（）。提示：缺氧可以刺激大鼠肺组织ｓｉｓｍＲＮＡ和ＰＤＧＦ－ＢＢ蛋白表达,其在缺氧性肺血管结构重塑形成中可能具有重要作用。     

PDGF-BB多肽刺激肺动脉平滑肌细胞PDGFmRNA表达

应用地高辛（Ｄｉｇｏｘｉｇｅｎｉｎ）标记的血小板源性生长因子（ＰＤＧＦ）Ａ和ＰＤＧＦＢ链ｃＤＮＡ探针,原位检测了ＰＤＧＦＢＢ多肽对单层培养的肺动脉平滑肌细胞ＰＤＧＦ基因表达的影响。结果表明,无血清培养的肺动脉平滑肌细胞内ＰＤＧＦＡ和ＰＤＧＦＢ链ｍＲＮＡ阳性表达颗粒稀少,ＰＤＧＦＢＢ多肽培养的肺动脉平滑肌细胞ＰＤＧＦＡ和ＰＤＧＦＢ链ｍＲＮＡ阳性表达颗粒增多,较密集的分布于整个细胞内。全自动图像分析结果显示,ＰＤＧＦＡ和ＰＤＧＦＢ链ｍＲＮＡ表达,ＰＤＧＦＢＢ培养组分别为无血清培养组的１７４倍和１７倍,差异显著（Ｐ＜００１）。本研究结果提示,ＰＤＧＦＢＢ多肽能刺激肺动脉平滑肌细胞ＰＤＧＦｍＲＮＡ表达,促进其分泌,在慢性低氧性肺动脉高压血管平滑肌细胞增殖中具有重要作用     

二甲基苯蒽对小鼠皮肤表皮鸟氨酸脱羧酶和转化生长因子βmRNA水平…

本文利用Ｎｏｒｔｈｅｒｎ印迹分析技术研究了完全致癌物二甲基苯蒽（ＤＭＢＡ）对小鼠表皮鸟氨酸脱羧酶（ＯＤＣ）ｍＲＮＡ和转化生长因子β（ＴＧＦ－β）ｍＲＮＡ水平的影响。ＤＭＢＡ在１５０μｇ和９００μｇ剂量下一次涂用于小鼠肝肤,可使表皮ＯＤＣ ｍＲＮＡ和ＴＧＦ－βｍＲＮＡ表达增加。ＯＤＣ ｍＲＮＡ为单一的２．０ｋｂ大小的条带,其表达在在３６ｈ时最为明显。而ＴＧＦ－βｍＲＮＡ大小为２．５ｋｂ和１．９ｋｂ,     

慢性缺氧大鼠肺血管c-myc及bcl-2基因表达研究

应用免疫组织化学和Ｎｏｒｔｈｅｒｎ杂交方法,对慢性缺氧大鼠肺组织（主要是肺血管壁）原癌基因ｃ－ｍｙｃ和抗凋亡基因ｂｃｌ－２表达进行了研究。免疫组织化学观察提示,正常对照组大鼠肺血壁Ｃ－ｍｙｃ和Ｂｃｌ－２蛋白仅为弱阳性或不表达,慢性缺氧１、２周组大鼠肺血管壁这两种抗原表达比对照组显著增强,呈强阳性,Ｎｏｒｔｈｅｒｎ杂交结果表明：慢性缺氧１、２周组大鼠肺组织内ｃ－ｍｙｃ和ｂｃｌ－２的ｍＲＮＡ表达比对照组显著增加,以上结果提示,ｃ－ｍｙｃ及ｂｃｌ－２两种基因调节的细胞增殖与凋亡可能参与了慢性缺氧性肺动脉高压的发病进程。     

二甲基苯蒽对小鼠皮肤表皮鸟氨酸脱羧酶和转化生长因子βmRNA水平的影响

本文利用Ｎｏｒｔｈｅｒｎ印迹分析技术研究了完全致癌物二甲基苯蒽（ＤＭＢＡ）对小鼠表皮鸟氨酸脱羧酶（ＯＤＣ）ｍＲＮＡ和转化生长因子β（ＴＧＦ－β）ｍＲＮＡ水平的影响。ＤＭＢＡ在１５μｇ和９００μｇ剂量下一次涂用于小鼠皮肤,可使表皮ＯＤＣｍＲＮＡ和ＴＧＦ－βｍＲＮＡ表达增加。ＯＤＣｍＲＮＡ为单一的２．０ｋｂ大小的条带,其表达在在３６ｈ时最为明显。而ＴＧＦ－βｍＲＮＡ大小为２．５ｋｂ和１．９ｋｂ,其表达在３６ｈ时最高,到４８ｈ几乎降至正常,但在７２ｈ又有增加。ＯＤＣ和ＴＧＦ－β可能在ＤＭＢＡ诱癌过程中起重要作用。     

动脉平滑肌细胞sis／PDGF—B链的表达和调控

介绍平滑肌细胞ｓｉｓ／ＰＤＧＦ－Ｂ链表达和调控的进展。ｃ－ｓｉｓ原癌基因是ＰＤＧＦ－Ｂ的同源基因,将外源的ＰＤＧＦ基因导入哺乳类细胞是研究ＰＤＧＦ功能和调控的重要手段。内皮素ＩＬ、ＴＮＦ、血管紧张素Ⅱ和蛋白激酶Ｃ可调节ｓｉｓ基因的表达。ｓｕｒａｍｉｎ和新霉素的人工合成为拮抗ＰＤＧＦ效应提供广阔的前景。ｃ－ｓｉｓ可通过激活ｃ－ｍｙｃ,ｃ－ｆｏｓ等原癌基因而促进细胞增殖。     

低氧对肺动脉平滑肌细胞PDGF mRNA表达的影响

应用原位杂交技术,研究了低氧对单层培养的猪肺动脉平滑肌细胞血小板源性生长因子（ＰＤＧＦ）－Ａ和－Ｂ链ｍＲＮＡ表达的影响。用全自动图像分析仪检测两组细胞ＰＤＧＦ－Ａ和－Ｂ链杂交产物的平均光密度值。结果表明：常氧条件下无血清培养的肺动脉平滑肌细胞ＰＤＧＦ－Ａ和－Ｂ链ｍＲＮＡ表达阳性颗粒稀少,低氧条件下血清培养的肺的动脉平滑肌细胞ＰＤＧＦ－Ｂ链ｍＲＮＡ表达阳性颗粒明显增多,较密集地分布于整个细胞内,为常     

动脉平滑肌细胞sis／PDGF－B链的表达和调控

介绍平滑肌细胞ｓｉｓ／ＰＤＧＦ－Ｂ链表达和调控的进展。ｃ－ｓｉｓ原癌基因是ＰＤＧＦ－Ｂ的同源基因,将外源的ＰＤＧＦ基因导入哺乳类细胞是研究ＰＤＧＦ功能和调控的重要手段。内皮素、ＩＬ、ＴＮＦ、血管紧张素Ⅱ和蛋白激酶Ｃ可调节ｓｉｓ基因的表达。ｓｕｒａｍｉｎ和新霉素（ｎｅｏｍｙｃｉｎ）的人工合成为拮抗ＰＤＧＦ效应提供广阔的前景。ｃ－ｓｉｓ可通过激活ｃ－ｍｙｃ、ｃ－ｆｏｓ等原癌基因而促进细胞增殖。     

碱性成纤维细胞生长因子对大鼠肾小球系膜细胞原癌基因c-fos和c-myc表达的影响

在建立大鼠肾小球系膜细胞（ＭＣ）体外培养方法的基础上,通过３Ｈ－ＴｄＲ参入实验,ＲＮＡ印迹分析和斑点杂交观察ｂＦＧＦ对ＭＣＤＮＡ合成及原癌基因ｃ－ｆｏｓ和ｃ－ｍｙｃ表达的影响．结果表明,ｂＦＧＦ作用于ＭＣ１８ｈ,ＭＣ的３Ｈ－ＴｄＲ参入率明显增加（Ｐ＜０．０５）,２４ｈ达到高峰（Ｐ＜０．０１）;ｂＦＧＦ显著诱导原癌基因ｃ－ｆｏｓ和ｃ－ｍｙｃ表达,其表达活性分别于３０ｍｉｎ和１ｈ达到高峰．提示ｂＦＧＦ是ＭＣ的强效丝裂原,其对ＭＣＤＮＡ合成的促进作用与诱导原癌基因ｃ－ｆｏｓ和ｃ－ｍｙｃ表达有关．     

Oncogene expression in vivo by ovarian adenocarcinomas and mixed-mullerian tumors

Six-micron paraffin sections of paraformaldehyde-fixed specimens of 24 ovarian benign and neoplastic specimens were assayed for tumor cell-specific oncogene expression by a sensitive, quantitative in situ hybridization technique with probes for 17 oncogenes, beta-actin, and E. coli beta-lactamase. In the benign, borderline, and invasive adenocarcinomas, multiple oncogenes, including neu, fes, fms, Ha-ras, trk, c-myc, fos, and PDGF-A chains, were expressed at significant levels relative to a housekeeping gene (beta-actin). In the mixed-Mullerian tumors, a rather different pattern of oncogene expression was observed, characterized primarily by expression of sis (PDGF-B chain). For the adenocarcinomas, statistical analysis demonstrated that expression of several genes (fms, neu, PDGF-A) was closely linked to others (c-fos, c-myc) known to have important roles in the control of cell proliferation, but only one gene, fms, correlated very strongly with clinicopathologic features (high FIGO histologic grade and high FIGO clinical stage) predictive of aggressive clinical behavior and poor outcome. The authors discuss the role that tumor epithelial cell expression of the fms gene product might play in the auto- and paracrine control of growth and dissemination of ovarian adenocarcinomas.     

Transforming growth factor-beta induces platelet-derived growth factor (PDGF) messenger RNA and PDGF secretion while inhibiting growth in normal human mammary epithelial cells

Platelet-derived growth factor (PDGF) is a potent mitogen in human serum which specifically stimulates the proliferation of mesenchymal cells. We have now examined normal human mammary epithelial cells (HMEC) derived from reduction mammaplasties and grown in a serum-free defined medium. Medium conditioned by HMEC contained a PDGF-like activity that competed with [125I]PDGF for binding to PDGF receptors in normal human fibroblasts. When conditioned media were incubated with antiserum specific for either PDGF-A or PDGF-B, only PDGF-A antiserum was capable of inhibiting binding of conditioned media to PDGF receptors. Using an RNase protection assay, mRNA from normal HMEC was probed for both the PDGF-A and PDGF-B chains. Little or no PDGF-B was found in HMEC strains, while a strong signal was seen with the PDGF-A probe. When HMEC were grown in the presence of transforming growth factor-beta (TGF beta) for 48 h, inhibition of growth was observed in association with a 20- to 40-fold stimulation of PDGF-B mRNA and a 2-fold stimulation of PDGF-A mRNA. This mRNA induction was extremely rapid (within 1 h), and secreted PDGF activity was induced 2- to 3-fold. Two other HMEC growth inhibitors and differentiating agents, sodium butyrate and phorbol ester 12-O-tetradecanoylphorbol-13-acetate, had no effect on PDGF mRNA regulation. The current study suggests that PDGF gene induction is an extremely rapid and specific indicator of TGF beta function regardless of whether TGF beta is acting in a growth stimulatory or inhibitory manner. Any role of PDGF-B in TGF beta modulation of differentiation of normal or malignant mammary gland remains to be determined.     

IL-4抑制COPD大鼠肺组织COX-2和PDGF的表达

目的探讨白细胞介素-4(IL-4)对慢性阻塞性肺疾病(COPD)大鼠模型建立的影响,以及COPD肺组织中环氧合酶-2(COX-2)和血小板源性生长因子(PDGF)的表达及IL-4对其表达的影响机制。方法用雄性Wistar大鼠建立吸烟大鼠COPD模型。随机分为对照组,模型组,IL-4组和地塞米松组。用免疫组化法和逆转录聚合酶联反应法(RT-PCR),检测肺组织中COX-2和PDGF-A及PDGF-B的表达情况。结果模型组COX-2和PDGF-A、-B表达明显增高;IL-4组和地塞米松组显著降低。结论IL-4和地塞米松可干预COPD模型的建立;COPD肺组织中COX-2和PDGF的表达显著增高,IL-4和地塞米松可明显降低其表达。     

Coexpression of tumor-associated alpha 2-macroglobulin and growth factors in human melanoma cell lines.

alpha 2-Macroglobulin (alpha 2M) is known as an inhibitor of various proteinases and to bind several of the growth factors. We previously demonstrated that clonal variation exists in the production of alpha 2M in a human melanoma and that this variation may be associated with growth stimulation. We have now analyzed six human melanoma cell lines for the simultaneous expression of TGF-alpha, TGF-beta, PDGF-A chain, PDGF-B chain, and tumor-associated alpha 2M. In Northern blot analysis TGF-alpha was detected in four of the cell lines, TGF-beta in all, PDGF-A chain in three, and PDGF-B chain in none of the cell lines. alpha 2M, detected by immunoblotting, varied significantly between the different melanoma cell lines and only one cell line was found to be negative. Evaluation of growth-promoting activity in conditioned media suggested that alpha 2-macroglobulin, secreted by these tumor cell lines, is a significant modulator of melanoma cell growth.     

Expression of platelet-derived growth factor proteins and their receptor α and β mRNAs during fracture healing in the normal mouse

Platelet-derived growth factor (PDGF), abundant in bone tissue, has been reported to stimulate mesenchymal cell proliferation and migration. To elucidate the functional roles of PDGF during fracture healing, we investigated the expression of PDGF-A and -B chain proteins and receptor α and β mRNAs in fractured mouse tibiae. Twelve-week-old male BALB/c mice were operated on to make a closed fracture on the proximal tibia. On days 2, 4, 7, 10, 14, 21, and 28 after the operation, the fractured tibiae were excised, fixed with 4% paraformaldehyde, decalcified with 20% EDTA, and embedded in paraffin to prepare 7-μm sections. Immunohistochemistry using polyclonal antibodies against human PDGF-A and -B chains was carried out by the avidin-biotin-peroxidase method. For in situ hybridization, we used digoxigenin-labeled single-stranded DNA probes specific for mouse PDGF receptors α and β generated by unidirectional polymerase chain reaction. In the inflammatory phase on days 2–4 after the fracture, mesenchymal cells gathering at the fracture site expressed the PDGF-B chain and β receptor mRNA. At the stage of cartilaginous callus formation on day 7, the immunoreactivity for PDGF-A and -B chains on proliferating and hypertrophic chondrocytes and the signals of α and β receptor mRNAs on proliferating chondrocytes became manifest. At the stage of bony callus and bone remodeling on days 14–21, the predominant expression of the PDGF-B chain and β receptor was observed on both osteoclasts and osteoblasts. On day 28, signals for PDGF ligand proteins and receptor mRNAs diminished. The coincidental localization of PDGF ligands and their receptors implies a paracrine and autocrine mechanism. Our data suggested that PDGF contributed in part to the promotion of the chondrogenic and osteogenic changes of mesenchymal cells from the early to the midphase of fracture healing; the functions mediated by the β receptor, including cell migration, might be prerequisites to the recruitment of mesenchymal cells in the initial step and to the interaction between osteoclasts and osteoblasts in the bone remodeling phase. Accepted: 2 June 1999