碱性成纤维细胞生长因子对兔正常和缺血心肌血管新生的影响

目的　观察碱性成纤维细胞生长因子 ( b FGF)对兔正常和缺血心肌血管新生的影响。方法　开胸结扎兔的冠状动脉左前降支 ( L AD)后 ,动物被随机分为两组 ,一组分别在兔缺血和正常的心肌内注入重组人类的 b FGF ( n=9) ,另一组分别注入生理盐水 ( n=7)。 6周后 ,观察两组兔子的缺血和正常心肌的血管新生情况。结果　注射rhb FGF后 ,缺血心肌的血管密度较注射生理盐水者有显著性增加 ,而正常心肌的血管密度未见明显增加。结论　rhb FGF能促进缺血心肌的血管生长但不能促进正常心肌的血管生长     

碱性成纤维细胞生长因子对肠道缺血所致肠道和肝损伤的影响

目的研究急性肠系膜上动脉夹闭后全身应用碱性成纤维细胞生长因子(bFGF)对肠道和肝的保护作用.方法采用夹闭大鼠肠系膜上动脉40 min 与再灌注72 h 动物模型.72只大鼠随机分成 bFGF 治疗组,肝素生理盐水对照治疗组以及假手术组.用肝功能指标,血浆 TNFa 含量,组织细菌学定量以及病理学方法评价伤后不同时间的治疗效果.结果经 bFGF 治疗的大鼠伤6 h 与24 h 的肝功能损伤较对照明显减轻,血浆 TNFa 含量显著减少.脏器细菌培养以现经bFGF 治疗的大鼠,其肠道细菌迁移至肝脾与淋巴结的发生率较对照治疗组明显下降.结论 bFGF 能显著减轻肠道缺血再灌注对肠道和肝形态与功能损伤.其作用机制可能与 bFGF 的促分裂效应与非促分裂激素样活性有关.     

碱性成纤维细胞生长因子基因对猪缺血心肌心功能的影响

目的探讨经导管冠状动脉内注射碱性成纤维细胞生长因子基因(pcDNA3-bFGF),对猪缺血心肌心功能的影响。方法构建真核表达质粒pcDNA3-bFGF。开胸结扎猪冠状动脉左回旋支(LCX),建立急性心肌梗死动物模型。实验动物分为三组:手术对照组(n=6),bFGF基因左冠状动脉注射组(n=6),bFGF基因右冠状动脉注射组(n=6)。术后2周,分别行选择性冠状动脉造影,并经导管冠状动脉内注射pcDNA3-bFGF2000μg。术后4周,通过超声心动图测定左心室射血分数(LVEF),评估左心室收缩功能,并再次行选择性冠状动脉造影,观察冠状动脉侧枝血管新生情况,并通过压力监测装置观察不同组动物左心室舒张末压(LVEDP)。结果(1)术后4周超声心动图示左、右冠状动脉注射基因组LVEF值高于手术对照组,LVDEP低于手术对照组;(2)选择性冠状动脉造影显示,术后4周左右冠状动脉注射基因组侧枝血管明显多于对照组,左冠状动脉注射基因组,侧枝血管多于右冠状动脉基因注射组。结论经导管冠状动脉内注射bFGF基因,能促进猪缺血心肌血管新生,改善缺血心肌血供,改善心功能。     

酸性成纤维细胞生长因子的神经保护作用

脑、脊髓神经细胞受损后，常常不能重建正确的树突和轴突联系，即使经过治疗，患者的预后仍不理想。大量的研究证实，神经系统损伤后各类生长因子、神经营养因子（NTF）可促进神经元存活和轴突再生。目前，国内外的研究主要集中在NTF、碱性成纤维细胞生长因子（bFGF）和酸性成纤维细胞生长因子（aFGF）上。近10年来，成纤维细胞生长因子的神经保护作用已得到确认，作者就aFGF在神经系统中的作用综述如下。     

重组人碱性成纤维细胞生长因子对缺血心肌血管结构的作用观察

目的　观察重组人碱性成纤维细胞生长因子 (rhb FGF)对缺血心肌血管结构的作用。方法　建立兔急性心肌梗死模型 ,将 rhb FGF直接四点注射入兔缺血心肌内 ,通过病理切片图像分析观察缺血心肌血管管壁及管腔变化情况。结果　 rhb FGF组与生理盐水组平均管壁厚度分别为 6周 :(2 0 .70± 9.94 ) μm,(18.88± 9.6 5 ) μm,P>0 .0 5 ;12周 :(2 9.87± 12 .96 )μm,(18.13± 11.33)μm,P<0 .0 1;管壁管腔比值分别为 6周 :0 .2 5± 0 .12 ,0 .2 4± 0 .0 2 ,P>0 .0 5 ;12周 :0 .33± 0 .14 ,0 .2 4± 0 .0 9,P >0 .0 5。结论　 rhb FGF促缺血心肌血管新生到一定时期 (可能小于 12周 ) ,血管数量不再增长 ,只是血管管腔增大 ,管壁增厚 ,发生血管重构。     

Purification and characterization of acidic fibroblast growth factor from bovine brain.

Acidic brain fibroblast growth factor has been purified a minimum of 35,000-fold to apparent homogeneity by a combination of differential salt precipitation, ion exchange chromatography, gel filtration, isoelectric focusing, and hydrophobic chromatography on a C4 reversed-phase HPLC column. Two microheterogeneous forms of the molecule are obtained with apparent molecular masses of 16,600 and 16,800 daltons. The mitogen is highly active with half-maximal stimulation of BALB/c 3T3 fibroblasts at about 40 pg/ml in an assay using incorporation of [methyl-3H]thymidine into DNA.     

碱性成纤维细胞生长因子基因对猪缺血心肌侧支血管生成的作用

目的探讨经导管冠状动脉内注射碱性成纤维细胞生长因子(bFGF)基因(pcDNA3-bFGF)对猪缺血心肌侧支血管生成的作用。方法实验猪分为3组:手术对照组(n=6)、bFGF基因左冠状动脉注射组(n=6)和bFGF基因右冠状动脉注射组(n=6)。开胸结扎冠状动脉左回旋支(LCX),建立急性心肌梗死动物模型。术后2周,分别行选择性冠状动脉造影,并经导管冠状动脉内注射pcD-NA3-bFGF 2 000μg。给药后2周,再次行选择性冠状动脉造影观察冠状动脉侧支血管形成情况,并通过病理切片光镜观察、免疫组化染色进行血管计数,观察猪缺血心肌侧支血管生成情况。结果(1)病理切片及免疫组化染色结果显示左、右冠状动脉注射基因组血管计数较对照组明显增加;(2)术后4周选择性冠状动脉造影显示左、右冠状动脉注射基因组侧支血管明显多于对照组,左冠状动脉注射基因组侧支血管多于右冠状动脉基因注射组。结论经导管冠状动脉内注射bFGF基因能促进猪缺血心肌侧支血管生成。     

酸性成纤维细胞生长因子片段脑室内及皮下注射对大鼠夜间摄食的影响

目的: 测定大鼠摄食量的变化来鉴定aFGF分子中具有调节摄食行为的活性部位, 并进一步经皮下注射有活性的片段, 观察对大鼠夜间摄食的影响, 以此确定该活性片段外周给药的有效性.方法: 将设计好的七种a F G F 分子片段a FGF-(1-15), [D-T r p6]-a FGF-(1-15),[ d e s ami n o P h e1 .D- T r p6] - a FGF- ( 1 - 1 5 ) ,[desaminoPhe1.Lys(ε-myristyl)16]-aFGF-(1-16),[Lys(ε-myristyl)16]-aFGF-(1-16), [D-Trp6.Lys(ε-myristyl)16]-aFGF-(1-16)及[Ala16] aFGF-(1-29),在无麻醉下于18:30-19:00从第三脑室留置的不锈钢导管微量注射, 然后在19:00, 22:00及07:00的时间点测定饲料箱内粉末饲料, 分别计算3 h(19:00-22:00)及12 h(19:00-7:00)的摄食量. 然后将发现具有生物活性的aFGF-(1-15)及[Ala16]aFGF-(1-29)两个片段经皮下注射给药, 测定夜间摄食量.结果: aFGF-(1-15)以每只大鼠200 ng脑室内给与后对摄食没有影响, 以每只大鼠400 ng脑室内给与后减少了大鼠的夜间摄食量(3 h:3.0±0.2 vs 2.1±0.2; 12 h: 18.5±0.5 vs 16.1±0.5, P<0.01); [Ala16]aFGF-(1-29)经脑室内投与, 无论是在每只大鼠200 ng(3 h: 4.9±0.2 vs 3.4±0.2; 12 h: 19.3±1.2 vs 17.3±1.1,P<0.01); 还是每只大鼠400 ng给药均减少了大鼠的夜间摄食量(3 h: 3.6±0.1 vs 1.6±0.2;12 h: 19.9±0.8 vs 16.4±1.6, P<0.01), 并且与aFGF-(1-15)相比, [Ala16] aFGF-(1-29)抑制摄食作用更明显; 其余五种aFGF片段脑室内注射无论每只大鼠200 ng还是在每只大鼠400ng, 对大鼠夜间摄食均没有影响. aFGF-(1-15)和[Ala16]aFGF-(1-29)以80、100、300 mg/kg大鼠皮下注射, 其中仅[Ala16]aFGF-(1-29), 300mg/kg皮下注射减少了大鼠的夜间摄食量(3 h:3.9±0.2 vs 2.1±0.3; 12 h: 19.8±0.5 vs 11.2±0.8, P<0.01), 其余种类和剂量对大鼠夜间摄食均没有影响.结论: aFGF氨基酸序列的N末端及用丙氨酸代替aFGF氨基末端中半胱氨酸残基对摄食调节发挥重要作用. 而第6位甘氨酸被右旋-色氨酸替代, 第1位苯丙氨酸去氨基, 第16位半胱氨酸被赖氨酸(ε-十四烷基)所代替, 均没有摄食调节活性. 部分活性片段外周给药同样可以发挥其生物活性.     

藻酸双酯钠协同酸性成纤维细胞生长因子促血管生成作用的研究

探讨藻酸双酯钠(PSS)在体内协同酸性成纤维细胞生长因子(aFGF)促缺血区微血管生成作用的可行性.结果表明,给药后第10天,髂动脉血管造影可见aFGF组及aFGF+PSS组血管密度较盐水组明显增加,PSS组血管密度未见明显增加;aFGF组及aFGF+PSS组肌组织间有大量均匀分布的微血管与盐水组比较差异显著(P<0.05).PSS组与盐水组比较无显著差异(P>0.05).aFGF+PSS组与aFGF组及PSS组均有显著差异(P<0.05).aFGF具有促缺血区微血管生成作用,PSS具有协同aFGF的促血管生成作用.     

Protective effect of non-mitogenic human acidic fibroblast growth factor on hepatocyte injury

Aim: To study whether non-mitogenic human acidic fibroblast growth factor (nm-haFGF) has protective effects on H(2)O(2)-induced hepatocyte injury in vitro and CCl(4)-induced hepatocyte injury in vivo. Methods: (i) HL-7702 hepatocytes were incubated with different concentrations of nm-haFGF for 12 h, and then the activity of lactate dehydrogenase (LDH) in culture medium was detected, and genomic DNA electrophoresis analysis was observed after being exposed to H(2)O(2) (8 mmol/L) for 4 h. Proximately, apoptotic rates and protein expressions of Bcl-2 and Bax of HL-7702 cell were detected after being exposed to H(2)O(2) (0.2 mmol/L) for 20 h. (ii) Being injected intraperitoneally with nm-haFGF, mice were treated with CCl(4) intraperitoneally to induce hepatic injury. Twenty-four hours later, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured and histopathologic changes were evaluated. Results: (i) In vitro tests: LDH activities and apoptotic rates decreased, the protein expression of Bcl-2 increased and Baxdecreased in nm-haFGF-treated groups at the concentrations of 100 150 and 200 ng/mL, compared with that in the model control group, which was treated with H(2)O(2) alone. The genomic DNA remained nearly intact at the concentrations of 150 and 200 ng/mL. (ii) In vivo tests: serum ALT and AST in nm-haFGF-treated groups (10 mug/kg and 20 mug/kg) were much lower as compared to the model control group, which was treated with CCl(4) alone. Histological examination showed that nm-haFGF markedly ameliorated hepatocytes vacuolation, cloudy swelling and inflammatory cells infiltration induced by CCl(4). Conclusion: nm-haFGF had protective effects against H(2)O(2)-induced hepatocyte injury in vitro and CCl(4)-induced acute liver injury in vivo.     

Effects of fibroblast growth factor and epidermal growth factor on the rate of growth of amniotic fluid-derived cells.

Primary cultures of cells derived from human and bovine amniotic fluid were cultivated in Dulbecco's modified Eagles medium with 20% fetal calf serum. Whereas increased concentrations of fetal calf or other types of serum bring about no further mitogenic response, the rate of growth of these cells was nevertheless sharply increased when 100 ng/ml of FGF was added to the culture media. The FGF induced mitogenic effect was statistically significant. EGF at 100 ng/ml had a less pronounced effect which, when analyzed statistically, was not significant. Amniotic fluid-derived cells are used for the prenatal detection of genetic disorders. The use of FGF to increase the rate of growth of these cells should reduce the time required between amniocentesis and diagnosis.     

Elevation of acidic fibroblast growth factor mRNA in lesioned rat brain

A 40-base oligodeoxynucleotide probe is described which has been prepared corresponding to the amino acid sequence 9-22 of acidic fibroblast growth factor. Following electrophoretic separation of rat brain mRNA under denaturing conditions the probe hybridizes to a major polyadenylated mRNA species of approximately 4.8 kb. This mRNA is the same size as that reported for acidic fibroblast growth factor mRNA. The relative abundance of the hybridizing 4.8 kb mRNA species increases in rat brain 3 days after cortical lesion indicating increased expression of the gene for acidic fibroblast growth factor.     

Structural evidence that endothelial cell growth factor beta is the precursor of both endothelial cell growth factor alpha and acidic fibroblast growth factor.

Two endothelial cell growth factors (ECGF) have been purified from bovine brain and termed alpha- and beta-ECGF [Burgess, W. H., Mehlman, T., Friesel, R., Johnson, W. V. & Maciag, T. (1985) J. Biol. Chem. 260, 11389-11392]. Amino acid sequence analysis indicates that beta-ECGF represents a 20 amino acid amino-terminal extension of alpha-ECGF and a 14 amino acid amino-terminal extension of acidic fibroblast growth factor. These data indicate that both alpha-ECGF and acidic fibroblast growth factor may be derived from beta-ECGF by posttranslational processing. Analysis of the amino-terminal 14 residues of beta-ECGF by fast-atom-bombardment mass spectrometry established the amino acid sequence of this region and the identity of the blocking group at the amino terminus (acetyl).     

bFGF促进缺血心肌血管生成和改善心肌功能的实验研究

目的利用生长因子通过诱导血管生成治疗缺血性心脏病,但生长因子的输入方式还存在一些争议。本研究旨在探讨心肌内注射碱性成纤维生长因子（bFGF）对急性心肌梗死（AM I）血管生成和心肌功能的作用。方法AM I犬24只,随机分成对照组（M I区注射生理盐水15 m l）和实验组（M I区注射50 mg bFGF与生理盐水的混合液15 m l）;每组观察4个不同的时间点（术后0、2、9、16 d）。各组动物分别在处死前应用敏感编码技术（sensitivity en-coded techn ique,SENSE）行磁共振电影成像（c ine m agnetic resonance im aging,c ine-MR I）;电镜直接观察新生血管生长情况;免疫组织化学方法检测各组微血管数量;以左心室射血分数（LVEF）评价心脏功能的改变。结果实验组LVEF自9 d明显增加[9 d:对照组（24±3）%、实验组（46±6）%;16 d:对照组（31±5）%、实验组（53±5）%];除0d外各个时间点的微血管数量实验组均比对照组明显增多[2 d:对照组（92±12）支/视野、实验组（147±12）支/视野;9 d:对照组（125±12）支/视野、实验组（183±14）支/视野;16 d:对照组（125±14）支/视野、实验组（224±20）支/视野]。结论心肌内注射bFGF具有促进M I区域毛细血管形成及改善左心室功能的作用。     

Hypoxia-mediated induction of acidic/basic fibroblast growth factor and platelet-derived growth factor in mononuclear phagocytes stimulates growth of hypoxic endothelial cells.

Wound repair and tumor vascularization depend upon blood vessel growth into hypoxic tissue. Although hypoxia slows endothelial cell (EC) proliferation and suppresses EC basic fibroblast growth factor (bFGF) expression, we report that macrophages (MPs) exposed to PO2 approximately 12-14 torr (1 torr = 133.3 Pa) synthesize and release in a time-dependent manner platelet-derived growth factor (PDGF) and acidic/basic FGFs (a/bFGFs), which stimulate the growth of hypoxic ECs. Chromatography of hypoxic MP-conditioned medium on immobilized heparin with an ascending NaCl gradient resolved three peaks of mitogenic activity: activity of the first peak was neutralized by antibody to PDGF; activity of the second peak was neutralized by antibody to aFGF; and activity of the third peak was neutralized by antibody to bFGF. Metabolically labeled lysates and supernatants from MPs exposed to hypoxia showed increased synthesis and release of immunoprecipitable PDGF and a/bFGF in the absence of changes in cell viability. Possible involvement of a heme-containing oxygen sensor in MP elaboration of growth factors was suggested by the induction of bFGF and PDGF by normoxic MPs exposed to nickel or cobalt, although metabolic inhibitors such as sodium azide were without effect. These results suggest a paracrine model in which hypoxia stimulates MP release of PDGF and a/bFGF, inducing EC proliferation and potentially promoting angiogenesis in hypoxic environments.     

Growth stimulation of rat calvaria osteoblastic cells by acidic fibroblast growth factor

Purified acidic fibroblast growth factor (aFGF) from bovine brain stimulates the proliferation of calvaria-derived osteoblastic cells. Maximum stimulation, relative to corresponding controls, was seen at 0.2% serum (2- to 3-fold), and no stimulation was seen in the absence of serum or under serum replete conditions. The effect was dose-dependent with an ED50 of around 750 pg/ml (47 pM). aFGF (5 ng/ml) sustained the growth of calvaria cells in culture during multiple passages (72 days) at 0.2% serum. In DNA synthesis assays aFGF produced 2- to 4-fold stimulation; insulin-like growth factor I had a slight effect on DNA synthesis on its own, but enhanced the effect of aFGF 2-fold. In cells fully stimulated by epidermal growth factor (5-fold), aFGF had no further effect. Stimulation of DNA synthesis peaked at 5 ng/ml, while higher concentrations were inhibitory. Recombinant aFGF (bovine sequence) also stimulated cell proliferation (1.5-fold), and its potency was augmented by heparin (50 micrograms/ml), about 2-fold. Using simultaneous histochemical staining for alkaline phosphatase activity and [3H]thymidine nuclear uptake we found that aFGF stimulates DNA synthesis to the same extent in alkaline phosphatase-rich (osteoblastic) and alkaline phosphatase-poor (nonosteoblastic) cells. However, after cell division there is a significant decrease in PTH-responsive adenylate cyclase (2- to 3-fold) and in alkaline phosphatase levels (4- to 8-fold). These findings indicate that aFGF is mitogenic to rat calvaria osteoblastic cells, its action requires additional factors, and its growth stimulation is associated with a reduction in phenotypic expression.     

Heparin-binding growth factor type 1 (acidic fibroblast growth factor): a potential biphasic autocrine and paracrine regulator of hepatocyte regeneration.

Heparin-binding growth factor type 1 (HBGF-1; sometimes termed acidic fibroblast growth factor) is potentially an important factor in liver regeneration. HBGF-1 alone (half-maximal effect at 60 pM) stimulated hepatocyte DNA synthesis and bound to a high-affinity receptor (Kd = 62 pM; 5000 per cell). Epidermal growth factor (EGF) neutralized or masked the mitogenic effect of HBGF-1 concurrent with appearance of low-affinity HBGF-1 binding sites. HBGF-1 reduced the inhibitory effect of transforming growth factor type beta (TGF-beta) on the EGF stimulus. Nanomolar levels of HBGF-1 decreased the EGF stimulus. An increase in hepatic HBGF-1 gene expression after partial hepatectomy precedes increases in expression of the EGF homolog, TGF-alpha, and nonparenchymal-cell-derived TGF-beta in the regenerating liver. Expression of HBGF-1 mRNA occurs in both hepatocytes and nonparenchymal cells and persists for 7 days in liver tissue after partial hepatectomy. HBGF-1 acting through a high-affinity receptor is a candidate for the early autocrine stimulus that drives hepatocyte DNA synthesis prior to or concurrent with the EGF/TGF-alpha stimulus. It may allow hepatocyte proliferation to proceed in the presence of low levels of TGF-beta. An EGF/TGF-alpha-dependent change in HBGF-1 receptor phenotype and increasing levels of nonparenchymal-cell-derived HBGF-1 and TGF-beta may serve to limit hepatocyte proliferation.     

Ultrasonic tissue characterization of normal and ischemic myocardium

Cardiac ultrasonic tissue characterization is designed to use the alterations in acoustic signals from the myocardium to differentiate normal from ischemic or infarcted tissue due to their characteristic backscatter attenuation. Various approaches such as use of a gray scale, color display, or quantitative image analysis have been used for tissue characterization, but all depend on subjective assessments and are not necessarily reproducible. The most promising method has been the use of "raw" radiofrequency signals and measure changes in the ultrasonic attenuation with an index of backscatter to distinguish normal from abnormal myocardium called "integrated backscatter" (IB). Various studies have demonstrated the changes in the ultrasonic backscatter with ischemia or infarction. In this review we summarize our experience with a research prototype instrument in tissue characterization and differentiation of normal, ischemic, infarcted, and post ischemic reperfused myocardium in anesthetized open chest dogs. Currently we are investigating the role of ultrasonic tissue characterization to estimate infarct size and plan to apply these observations to patients in order to detect viable myocardium and quantitate infarct size.