血小板激活因子受体拮抗剂在肺动脉高压中的应用

血小板激活因子在肺动脉高压的发病中可能起着重要的介导作用。目前已发现的特异性血小板激活因子受体拮抗剂有多种，它们能在受体水平拮抗血小板激活因子的各种生物效应，对血小板激活因子，低氧及野百合碱等所致的肺动脉增压作用起着一定的预防和治疗作用。     

血小板激活因子受体拮抗剂在肺动脉高压中的应用

血小板激活因子在肺动脉高压的发病中可能起着重要的介导作用。目前已发现的特异性血小板激活因子受体拮抗剂有多种,它们能在受体水平拮抗血小板激活因子的各种生物效应,对血小板激活因子、低氧及野百合碱等所致的肺动脉增压作用起着一定的预防和治疗作用。     

血小板活化因子受体拮抗剂干扰实验性肾炎的疗效观察及机理探讨

实验大鼠均制成加速型抗肾小球基膜（GBM）肾炎模型，分为三组：模型组、血小板活化因子（PAF）受体拮抗剂BN－52021组和血栓素A2（TXA2）合成酶抑制剂UK－38485组，结果BN－52021组大鼠各期尿蛋白量较模型组显著减少（P＜0．01），第21天时血清肌酐、肾皮质内TXB2含量较模型组显著降低（P＜0．01）；光镜和电镜下肾组织病理改变明显较模型组为轻；UK-8485组尿蛋白量也倾向于较模型组减少，担无统计学意义．第21天时血清肌酐、肾皮质内TXB2含量也较模型组显著降低（P＜0．01）．本实验表明，PAF受体拮抗剂干扰该大鼠肾炎有效，其有效机理可能部分是通过减少肾皮质TXA2合成而介导的。     

血小板活化因子在病毒性肝炎中的变化及意义

目的　探讨血小板活化因子 (PAF)、血清肿瘤坏死因子α(TNF α)、丙二醛 (MDA)和血浆内毒素 (ET)等指标在病毒性肝炎中的变化和意义。方法　分别采用反相高效液相色谱测定法(rHPLC)和生物学法、双抗体夹心酶联免疫吸附试验 (ELISA)、鲎试验 (LLT)、硫化巴比妥酸法 (TBA)对 6 0例健康对照者、2 1例急性肝炎、85例慢性肝炎、2 6例重型肝炎患者进行血PAF、TNF α、ET和MDA等指标的测定、分析。结果　rHPLC法与生物学法比较 ,两者呈较好的相关性 (r =0 .912 )。肝炎患者血PAF、TNF α、内毒素和MDA值均明显高于正常对照组 (P <0 .0 1)。重型肝炎患者血中PAF水平与ET、TNF α水平呈显著正相关 (r =0 .892 ,P <0 .0 1;r =0 .76 7,P <0 .0 1) ;血清TNF α水平与内毒素水平成正相关 (r =0 .86 3,P <0 .0 1)。结论　rHPLC法测定PAF可靠 ,能正确地反映血中PAF水平 ;联合测定血PAF、MDA、ET、TNF α有助于检测病毒性肝炎的进行性损害程度及预后判断 ,有助于推动病毒性肝炎的基础与临床研究。     

血小板活化因子受体拮抗剂对幼年大鼠肠黏膜上皮细胞间紧密连接蛋白的影响

目的:探讨血小板活化因子(platelet activating factor,PAF)受体拮抗剂对肠黏膜上皮细胞间紧密连接蛋白ZO-1的影响．方法:18日龄Wistar大鼠,随机分为对照组,内毒素组(LPS组)和PAF受体拮抗剂组(预防组和治疗组)．LPS组和对照组分别腹腔注射内毒素 (5 mg/kg)和生理盐水(1 mL/kg)．预防组和治疗组分别于每一时相点注射LPS前、后30 min 腹腔注射PAF受体拮抗剂BN52021(5 mg/kg)．按时间点分别处死动物,取回肠用于电镜观察,免疫组化及RT-PCR检测ZO-1．结果:电镜下对照组肠微绒毛及细胞间紧密连接未见异常．实验组上皮细胞连接增宽;微绒毛变细、稀疏,部分断裂、脱落;细胞器受损．拮抗剂组改变较实验组减轻．紧密连接蛋白ZO-1正常时均匀一致地分布于小肠上皮细胞连接处的尖端,呈蜂巢状,实验组ZO-1 分布不均,染色变淡．免疫组化平均光密度值及RT-PCR结果可见LPS组ZO-1表达明显低于对照组,6 h表达最低,光密度从对照组 0．224 7降至LPS组0．198 5,ZO-1 mRNA从1．18 降至0．16(P<0．01)．预防组及治疗组变化趋势同LPS组,6 h预防组及治疗组光密度分别为 0．199 2和0．203 8,ZO-1 mRNA分别为0．47和 0．53,与对照组相比均有显著差异(P<0．01)．各时相点ZO-1较LPS组高,预防组较治疗组 ZO-1略低,无统计学差异．结论:PAF可降低肠道紧密连接蛋白ZO-1,从而损害肠道的屏障功能,而PAF受体拮抗剂可减轻肠道屏障功能损伤的程度．     

PGE2在内毒素诱导的幼鼠急性胃黏膜损伤中的变化及PAF受体拮抗剂对其影响

目的:探讨前列腺素E2(PGE2)在内毒素(LPS) 腹腔注射(ip)诱导的幼鼠急性胃黏膜损伤中的保护作用．方法:18日龄Wistar大鼠,随机分为对照组、 LPS组、PAF受体拮抗剂预防组和治疗组四组.用内毒素(E coli O55:B5脂多糖)5 mg／kg ip 制备幼年大鼠内毒素血症模型,同等量生理盐水ip为对照组,于注射后1．5,3,6,24,48． 72 h处死动物,大体及光学显微镜下观察胃黏膜损伤情况,用放射免疫方法测定胃黏膜 PGE2浓度．观察分别于内毒素ip前和注射后 0．5h应用血小板活化因子(PAF)受体拮抗剂 BN52021(GinkgolideB)5 mg/kg ip对胃黏膜损伤和胃黏膜PGE2浓度影响．结果:内毒素组6h胃黏膜损伤最重,黏膜表面可见大片糜烂、出血、条索状坏死,光镜下上皮脱落,黏膜内有出血,核碎裂、固缩,凋亡小体出现;应用PAF受体拮抗剂后黏膜表面上皮仅见充血水肿,光镜下损伤仅限于黏膜上皮:内毒素组6h胃黏膜PGE2浓度最低,此时 PGE2浓度在LPS组(134．5±9.3μg／L)与对照组 (245．1±8．9 μg／L)间差异显著(P<0．01);在PAF 受体拮抗剂预防组(304．4±15．0μg／L)、PAF 受体拮抗剂治疗组(315．9±43．7 μg／L)与LPS 组(134．5±9．3 μg／L)间均差异显著(P<0．01); PAF受体拮抗剂预防组(304．4±15．0μg／L)和治疗组(315．9±43．7μg／L)与对照组(245．1± 8．9μg/L)间差异显著(P<0．05)．结论:内毒素血症时胃黏膜PGE2下降,PAF受体拮抗剂可以改善这种PGE2下降;PGE2对内毒素造成的幼鼠急性胃黏膜损伤有保护作用．     

内皮素受体拮抗剂预防低氧性肺动脉高压的实验研究

内皮细胞合成的内皮素(ＥＴ)具有极强的促肺血管平滑肌细胞收缩和增生的作用。慢性低氧可引起血浆及肺组织匀浆中ＥＴ1水平升高,ＥＴ通过与ＥＴ1选择性受体(ＥＴＡ)或非选择性受体(ＥＴＢ)结合,参与慢性低氧性肺动脉高压的发病过程。为进一步探讨ＥＴ在低氧性肺动脉高压发病中的作用,本研究采用ＥＴＡ受体拮抗剂ＢＱ123进行预防处理,观察其对低氧性肺动脉高压的预防效应。一、材料和方法1动物模型的复制:雄性Ｗｉｓｔａｒ大鼠30只,体重200～220ｇ。分为低氧组、ＢＱ123组和对照组,每组10只。低氧组:将大鼠置于自制常压低氧舱内,向舱内充入氮…     

PAF受体拮抗剂对内毒素血症幼年大鼠胃黏膜NO含量及iNOS表达的影响

目的:探讨一氧化氮(NO)、诱导型一氧化氮合酶(iNOS)及PAF受体拮抗剂在内毒素(LPS)腹腔注射诱导的幼年大鼠急性胃黏膜损伤中的作用.方法:Wistar大鼠, 随机分为对照组、LPS组、PAF受体拮抗剂预防组和治疗组. 用内毒素(O55:B5脂多糖)5 mg/kg ip制备幼年大鼠内毒素血症模型. 预防组和治疗组分别于内毒素ip前及ip后0.5 h, 应用血小板活化因子(PAF)受体拮抗剂BN52021(GinkgolideB)5 mg/kg ip, 同等量生理盐水ip为对照组. 于LPS注射后1.5,3, 6, 24, 48, 72 h处死动物, 大体及光学显微镜下观察胃黏膜损伤情况, 采用硝酸还原酶的化学比色法测定胃黏膜NO含量;免疫组织化学S-P方法测定胃黏膜iNOS蛋白的表达, 半定量RT-PCR法测定胃黏膜iNOS mRNA的表达.结果:LPS组6 h胃黏膜损伤最重, 黏膜内有出血, 核碎裂、固缩, 凋亡小体出现;预防组和治疗组改变轻微. LPS组腹腔注射内毒素后6 h胃黏膜NO含量最高, 此时LPS组较对照组NO含量明显增高(84.37±5.44 vs 37.37±1.90,P<0.01), 预防组和治疗组(40.07±3.42, 48.63±3.24)较LPS组明显降低( P<0.01);预防组与治疗组较对照组明显增高( P<0.05). 对照组胃黏膜组织未见iNOS蛋白及mRNA的表达;LPS组腹腔注射内毒素后1.5 h胃黏膜组织胞质iNOS蛋白表达, 6 h明显增高, 24 h最高, 48 h下降, 72 h仍未恢复正常;预防组和治疗组3 hiNOS蛋白表达, 6 h明显增高, 48 h下降, 72 h同对照组. iNOS mRNA水平的表达变化与iNOS蛋白表达变化趋势相同.结论:PAF受体拮抗剂可下调iNOS mRNA表达水平, 减少iNOS蛋白表达, 使NO含量下降.从而使NO和iNOS对胃黏膜发挥保护作用.     

肿瘤坏死因子-α拮抗剂用于结缔组织病相关肺动脉高压的治疗

肺动脉高压（pulmonary arterial hypertension，PAH）是结缔组织病（connec tivetissue disease，CTD）常见且严重的并发症之一，与特发性肺动脉高压相比较，其生存率更低。目前PAH的发病机制尚不明确，但有证据显示肿瘤坏死因子-α（TNF-α）在结缔组织病和肺动脉高压发病过程中起重要作用，并且血清TNF-α升高与CTD-PAH的疾病进展相关。新开发的生物制剂（infliximab，etanercept，adalimumab）能够选择性阻断TNF-α，从而为PAH的治疗提供了新的机会。     

Effect of platelet-activating factor (PAF) receptor antagonist (BN52021) on acetaminophen-induced acute liver injury and regeneration in rats.

BACKGROUND: Platelet-activating factor (PAF) is an endogenous lipid mediator that plays a key role in catalyzing various pro-inflammatory processes associated with acute liver injury. In the present study, the possible influence of PAF-R antagonist (BN52021) on the protection of liver injury after 4-hydroxyacetanilide, N-acetyl-p-aminophenol, paracetamol (APAP) intoxication was investigated. METHODS: Thereby, one group of rats was treated with a toxic dose of APAP (3.5 g/kg body weight (b.w.). The animals were killed at 56, 66, 72, 84 and 96 h after treatment. RESULTS: APAP was found to cause an acute hepatic injury, evident by alterations of biochemical (serum enzymes: aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase) and liver histopathological (degree of necrosis and apoptosis) indices, which was followed by liver regeneration, evident by three independent indices ([3H] thymidine incorporation into hepatic DNA, liver thymidine kinase activity and hepatocyte mitotic index). The protective effects of BN52021 were qualified during post-treatment time by: (1) significant reduction of hepatic injury as showed by all biochemical and histological parameters, (2) high decrease of regenerating activity showed by three regenerative markers and (3) remarkable increase of PAF-acetylhydrolase (PAF-AH) activity. CONCLUSION: These results suggest that PAF may play an important role in APAP-induced liver injury and regeneration, and PAF-R antagonist (BN52021) attenuates liver damage.     

Significance of platelet activating factor receptor expression in pancreatic tissues of rats with severe acute pancreatitis and effects of BN52021

AIM:To investigate the dynamic changes and significance of platelet activating factor receptor (PAF-R) mRNA and protein in pancreatic tissues of rats with severe acute pancreatitis (SAP) and effects of BN52021 (Ginkgolide B). METHODS:Wistar male rats were randomly assigned to the negative control group (NC group),SAP model group (SAP group),and BN52051-remedy group (BN group),and each of the groups was divided into 6 subgroups at different time points after operation (1 h,2 h,3 h,6 h,12 h,and 24 h) (n=10 in each). PT-PCR and Western blot methods were used to detect PAF-RmRNA and protein expression in pancreatic tissues of rats respectively. Pathological examination of pancreatic tissues was performed and the serum amylase change was detected. RESULTS:Serum amylase and pathological results showed the that SAP model was successfully prepared,BN52021 was able to decrease serum amylase,and the pathological ratings in BN group at 3 h,6 h,and 12 h significantly decreased compared with those in the SAP group (8.85 ± 0.39 vs 5.95 ± 0.19,9.15 ± 0.55 vs 5.55 ± 0.36,10.10 ± 0.65 vs 6.72 ± 0.30,P < 0.05). The result of PAF-mRNA showed dynamic changes in SAP and BN groups,which increased gradually in early stage,reached a peak at 3 h (0.71 ± 0.14 vs 0.54 ± 0.14,0.69 ± 0.13 vs 0.59 ± 0.04,P < 0.05),and decreased gradually later. There were significant differences at each time point except 1 h and 2 h,when compared with those in the NC group (0.71 ± 0.14 or 0.69 ± 0.13 vs 0.47 ± 0.10,0.38 ± 0.08 or 0.59 ± 0.04 vs 0.47 ± 0.09,0.25 ± 0.07 or 0.29 ± 0.05 vs 0.46 ± 0.10,0.20 ± 0.06 or 0.20± 0.04 vs 0.43 ± 0.09,P < 0.05),whereas there was no significant difference between BN and SAP groups at each time point. The result of PAF-R protein showed that the change of PAF-R protein in the SAP group and the BN group was consistent with that of PAF-R mRNA. There were significant differences at each time point except 1 h,when compared with those in the NC group (0.90 ± 0.02 or 0.80 ± 0.05 vs 0.48 ± 0.02,1.69 ± 0.06 or 1.58 ± 0.02 vs 0.48 ± 0.03,1.12 ± 0.10 or 0.98 ± 0.03 vs 0.49 ± 0.09,1.04 ± 0.14 or 0.87 ± 0.02 vs 0.52 ± 0.08,0.97 ± 0.16 or 0.90 ± 0.05 vs 0.49 ± 0.10,P < 0.05),whereas there was no significant difference between the BN group and the SAP group. CONCLUSION:PAF-R plays an important role in occurrence and development of SAP. BN52021 exerts biological effects through competitively inhibiting the binding of increased both PAF and PAF-R expression rather than through decreasing PAF-R expression in pancreatic tissues.     

Roles of BN52021 in platelet-activating factor pathway in inflammatory MS1 cells

AIM: To determine the effects of BN52021 on platelet-activating factor receptor (PAFR) signaling molecules under lipopolysaccharide (LPS)-induced inflammatory conditions in MS1 cells. METHODS: MS1 cells (a mouse pancreatic islet endothelial cell line) were grown in Dulbecco’s modified Eagle’s medium supplemented with 10% fetal bovine serum, 2 mmol/L glutamine and 100 μg/mL penicillin/streptomycin in 5% CO 2 at 37 ℃. After growth to confluency in media, the cells were processed for subsequent studies. The MS1 cells received 0, 0.1, 1 and 10 μg/mL LPS in this experiment. The viability/prolifera-tion of the cells induced by LPS was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Apoptosis and necrosis of the cells under the inflammatory condition described previously were observed using Hoechst 33342-propidium iodide staining. Adenylate cyclase (AC), phospholipase A 2 (PLA 2 ), phospholipase Cβ (PLCβ), protein tyrosine kinase (PTK), G protein-coupled receptor kinases (GRK) and p38-mitogen-activated protein kinase (p38 MAPK) mRNA in the PAFR signaling pathway were measured by real-time polymerase chain reaction. The protein expression level of phosphorylated AC (p-AC), phosphorylated PLA 2 (p-PLA 2 ), phosphorylated PTK (p-PTK), phosphorylated p38 MAPK (p-p38 MAPK), PLCβ and GRK was measured using Western blotting analysis. RESULTS: The activity of MS1 cells incubated with dif- ferent concentrations of LPS for 6 h decreased significantly in the 1 μg/mL LPS group (0.49 ± 0.10 vs 0.67 ± 0.13, P < 0.05) and 10 μg/mL LPS group (0.44 ± 0.10 vs 0.67 ± 0.13, P < 0.001), but not in 0.1 μg/mL group. When the incubation time was extended to 12 h (0.33 ± 0.05, 0.32 ± 0.03 and 0.25 ± 0.03 vs 0.69 ± 0.01) and 24 h (0.31 ± 0.01, 0.29 ± 0.03 and 0.25 ± 0.01 vs 0.63 ± 0.01), MS1 cell activity decreased in all LPS concentration groups compared with the blank control (P < 0.001). BN52021 significantly improved the cell activity when its concentration     

Effect of BN52021 on NFκ-Bp65 expression in pancreatic tissues of rats with severe acute pancreatitis

AIM: To investigate dynamic changes and significance of expression of NF-κBp65 in pancreatic tissues of rats with severe acute pancreatitis (SAP), as well as BN52021 effects.METHODS: Wistar male rats were randomly divided into negative control group (NC group, n = 60), SAP-model group (SAP group, n = 60), and BN52021-treated group (BN group, n = 60), and each of the above groups was respectively divided into 6 subgroups at different time points after operation (1 h, 2 h, 3 h, 6 h, 12 h, and 24 h) (n = 10). By RT-PCR and Western blot, NF-KBp65 mRNA and its protein expression in pancreatic tissues of rats were detected respectively.RESULTS: The expression of NF-KBp65 mRNA dynamically changed in both SAP groups and BN groups. The mRNA level was higher in SAP groups than NC groups at 2 h, 3 h, 12 h, and 24 h after operation (P < 0.05), higher in BN groups than NC groups at all time points (P < 0.05), and higher in BN groups than SAP group at 1 h (P < 0.05). The NF-jcBp65 protein level was higher in SAP groups than NC groups at 1 h, 3 h, and 6 h (P < 0.01), and 2 h, 12 h, and 24 h (P < 0.05), higher in BN groups than NC groups at all time points (P < 0.05), and lower in BN groups than SAP groups at 1 h, 3 h, and 6 h (P < 0.05).CONCLUSION: The expression of NF-icBp65 in pancreatic tissues is dynamically changed and the changes play an important role in pathogenesis of SAP. BN52021 exerts therapeutic effects through reducing the expression level of NF-κBp65 protein in the early stage of SAP.     

Effect of BN52021 on NFκ-Bp65 expression in pancreatic tissues of rats with severe acute pancreatitis

AIM： To investigate dynamic changes and significance of expression of NF-κBp65 in pancreatic tissues of rats with severe acute pancreatitis （SAP）, as well as BN52021 effects.
METHODS： Wistar male rats were randomly divided into negative control group （NC group, n = 60）, SAP-model group （SAP group, n = 60）, and BN52021-treated group （BN group, n = 60）, and each of the above groups was respectively divided into 6 subgroups at different time points after operation （1 h, 2 h, 3 h, 6 h, 12 h, and 24 h） （n = 10）. By RT-PCR and Western blot, NF-κBp65 mRNA and its protein expression in pancreatic tissues of rats were detected respectively.
RESULTS： The expression of NF-κBp65 mRNA dynamically changed in both SAP groups and BN groups. The mRNA level was higher in SAP groups than NC groups at 2 h, 3 h, 12 h, and 24 h after operation （P 〈 0.05）, higher in BN groups than NC groups at all time points （P 〈 0.05）, and higher in BN groups than SAP group at 1 h （P 〈 0.05）. The NF-κBp65 protein level was higher in SAP groups than NC groups at 1 h, 3 h, and 6 h （P 〈 0.01）, and 2 h, 12 h, and 24 h （P 〈 0.05）, higher in BN groups than NC groups at all time points （P 〈 0.05）, and lower in BN groups than SAP groups at 1 h, 3 h, and 6 h （P 〈 0.05）.
CONCLUSION： The expression of NF-κBp65 in pancreatic tissues is dynamically changed and the changes play an important role in pathogenesis of SAR BN52021 exerts therapeutic effects through reducing the expression level of NF-κBp65 protein in the early stage of SAR     

Therapy for acute pancreatitis with platelet-activating factor receptor antagonists

Acute pancreatitis （AP） causes release of platelet-activating factor （PAF）, which induces systemic effects that contribute to circulatory disturbances and multiple organ failure. PAF is a cell surface secretion of bioactive lipid, which could produce physiological and pathological effects by binding to its cell surface receptor called platelet-activating factor receptor （PAF-R）. Studies showed that PAF participates in the occurrence and development of AP and administration of platelet-activating factor receptor antagonists （PAF-RAs） could significantly reduce local and systemic events after AP. PAF has also been implicated as a key mediator in the progression of severe AP, which can lead to complications and unacceptably high mortality rates. Several classes of PAF-RA show PAF- RAs significant local and systemic effects on reducing inflammatory changes. As a preventive treatment, PAF-RA could block a series of PAF-mediated inflammatory injury and thus improve the prognosis of AP. This review introduces the important role of PAF-RA in the treatment of AP.     

Role of endogenous platelet-activating factor (PAF) in endotoxin-induced portal hypertension in rats

To determine the role of platelet-activating factor (PAF) in endotoxin-induced portal hypertension, we performed continuous recording of both blood pressure (BP) and portal venous pressure (PVP) in rats following the administration of intravenous PAF (25 ng/kg), intraportal PAF (25 ng/kg), intraportal endotoxin (2 mg/kg), and intraportal endotoxin (2 mg/kg) for 1 min subsequent to pretreatment with a specific PAF-antagonist (CV-6209, 1 mg/kg, i.v.). Basal resting values of both BP (102.3 +/- 9.3 mmHg) and PVP (7.7 +/- 1.2 mmHg) fell rapidly after intravenous infusion of PAF (BP: 36.7 +/- 5.8 mmHg; PVP: 5.7 +/- 0.8 mmHg) and followed by gradual return. Intraportal PAF infusion elicited a rapid but less severe depression of BP (57.2 +/- 9.4 mmHg) as compared with intravenous PAF infusion, whereas PVP was increased transiently around 4 min after treatment (11.0 +/- 5.3 mmHg). A similar degree of PVP elevation (10.7 +/- 2.0 mmHg) was observed between 8 and 20 min after intraportal administration of endotoxin. Depression of BP was initiated 12 min after endotoxin administration but was not severe (76.6 +/- 12.8 mmHg). CV-6209 significantly alleviated the endotoxin-induced elevation of PVP and completely inhibited the hypotension. These observations suggest that: (i) PAF-induced elevation of PVP is a direct response of the liver to PAF; and (ii) endogenous PAF plays an important role in the endotoxin-induced portal hypertension.     

心力衰竭患者血小板活化因子及其受体表达的变化

目的 :探讨心力衰竭患者血浆血小板活化因子 (PAF)、血小板活化因子乙酰水解酶 (PAF AH)活性的变化 ,以及外周血中单个核细胞 (PBMC)PAF受体 (PAF R)的表达。方法 :对 30例心力衰竭患者采用生物法检测血浆中PAF含量 ,酶水解底物显色法测定PAF AH活性 ,流式细胞仪检测PBMC上PAF R的表达。并与 30例健康体检者对照。结果 :心力衰竭患者血浆中PAF含量 (11.12± 1.80 ) μg L ,PAF AH活性 (2 4 .5 0± 7.86 ) μmol (min·L)、PBMC上PAF R的表达与健康体检者比较差异有非常显著性意义 (P <0 .0 1)。结论 :PAF、PAF AH、PAF R三者在心力衰竭发生和发展中起重要作用     

粒细胞集落刺激因子对大鼠肺动脉高压模型的影响

目的:探讨粒细胞集落刺激因子(G-CSF)对野百合碱(MCT)诱导的大鼠肺动脉高压(PAH)的治疗作用。方法:动物随机分为3组:正常对照组(CON组)、MCT组和MCT/G-CSF组,腹腔注射MCT诱导大鼠PAH模型,采用G-CSF腹腔注射动员自体骨髓干细胞(BMSC),动员结束后行肺组织CD34免疫组化染色,第5周分别对3组大鼠进行血流动力学检测,处死大鼠,取肺、右心组织行苏木素-伊红(HE)染色。结果:1.动员结束后第2天,CD34+细胞浸润至肺血管平滑肌层和血管内皮细胞周围,以及肺泡间隔内;2.实验第35天,MCT组大鼠肺小动脉管壁增厚、管腔明显狭窄,血流动力学指标明显高于CON组(P<0.01);3.MCT/G-CSF组肺血管病变明显改善、肺泡结构完整,血流动力学指标明显低于MCT组(P<0.05)。结论:G-CSF可以动员骨髓干细胞并归巢致受损肺组织内,部分逆转PAH的血流动力学和病理学改变、减缓PAH的进展,用于PAH的研究和治疗。     

Synthesis of platelet-activating factor and its receptor expression in Kupffer cells in rat carbon tetrachloride-induced cirrhosis

AIM： To determine the platelet-activating factor （PAF） synthesis and its receptor expression in Kupffer cells in rat carbon tetrachloride-induced cirrhosis.
METHODS： Kupffer cells, isolated from the livers of control and CCl4-induced cirrhotic rats, were placed in serum-free medium overnight. PAF saturation binding, ET-1 saturation and competition binding were assayed. ET-1 induced PAF synthesis, mRNA expression of PAF, preproendothelin-1, endothelin A （ETA） and endothelin B （ETB） receptors were also determined.
RESULTS： A two-fold increase of PAF synthesis （1.42 ± 0.14 vs 0.66 ± 0.04 pg/μg DNA） and a 1.48-fold increase of membrane-bound PAF （1.02 ± 0.06 vs 0.69 ± 0.07 pg/μg DNA） were observed in activated Kupffer cells of cirrhotic rats. The application of ET-1 to Kupffer cells induced PAF synthesis in a concentration-dependent manner in both cirrhotic and normal rats via ETB receptor, but PAF synthesis in the activated Kupffer cells was more effective than that in the normal Kupffer cells. In activated Kupffer cells, PAF receptor expression and PAF binding capacity were markedly enhanced. Activated Kupffer cells raised the [^125I]-ET-1 binding capacity, but changed neither the affinity of the receptors, nor the expression of ETA receptor.
CONCLUSION： Kupffer cells in the course of CCl4- induced cirrhosis are the main source of increased PAF. ET-1 is involved endogenously in stimulating the PAF synthesis in activated Kupffer cells via ETB receptor by paracrine. ETA receptor did not appear in activated Kupffer cells, which may exacerbate the hepatic and extrahepatic complications of cirrhosis.