Oxidized phospholipids and lipoprotein-associated phospholipase A_2 as important determinants of Lp(a) functionality and pathophysiological role

Lipoprotein（a） [Lp（a）] is composed of a low density lipoprotein（LDL）-like particle to which apolipoprotein（a）[apo（a）] is linked by a single disulfide bridge. Lp（a） is considered a causal risk factor for ischemic cardiovascular disease（CVD） and calcific aortic valve stenosis（CAVS）. The evidence for a causal role of Lp（a） in CVD and CAVS is based on data from large epidemiological databases, mendelian randomization studies, and genome-wide association studies. Despite the well-established role of Lp（a） as a causal risk factor for CVD and CAVS, the underlying mechanisms are not well understood. A key role in the Lp（a） functionality may be played by its oxidized phospholipids（OxPL） content. Importantly, most of circulating OxPL are associated with Lp（a）; however, the underlying mechanisms leading to this preferential sequestration of OxPL on Lp（a） over the other lipoproteins,are mostly unknown. Several studies support the hypothesis that the risk of Lp（a） is primarily driven by its OxPL content.An important role in Lp（a） functionality may be played by the lipoprotein-associated phospholipase A_2（Lp-PLA_2）,an enzyme that catalyzes the degradation of OxPL and is bound to plasma lipoproteins including Lp（a）. The present review article discusses new data on the pathophysiological role of Lp（a） and particularly focuses on the functional role of OxPL and Lp-PLA_2 associated with Lp（a）.

Phospholipase A_2 and Its Relationship with Acute Lung Injury in Acute Pancreatitis in Dogs

Acute fulminant pancreatitis was produced in dogs by injection of autobile into the main pancreatic duct.After injection the phospholipase A_2(PLA_2)activities in serum,lung lymph and bronchoalveolar lavage fluid(BAL)were elevated significantly,lung lymph flow and pulmonary transvascular potein clearance increased progressively,protein content and cell numbers in BAL in the experimental animals were significantly higher than those in the control animals.Furthermore the lung index,wet to dry lung weight ratio,extravascular lung water to bloodless dry lung weight ra- tio,extravascuar lung water to bloodless dry lung weight ratio increased significantly as compared to control animals.Pretreatment with PLA_2 inhibitor,chloroquine,blocked the changes mentioned above.This experiment suggests:1.PLA_2 activity in lung lymph fluid as well as in serum and BAL is elevated in acute hemorrhagic pancreatitis.2.Elevated PLA_2 activity may increase the pulmonary vascular permeability.3.PLA_2 is the major factor leading to pulmonary edema in acute hemorrhagic pancreatitis.4.Phagocytes contribute to the lung injury induced by PLA_2 to some ex- tent.

CONTROL OF ANGIOGENESIS BY INHIBITOR OF PHOSPHOLIPASE A_2

Objective To investigate the potential effects of angiogenic process by secretory phospholipase A2 (sPLA2)inhibitor-HyPE(linking N-derivatized phosphatidyl-ethanolamine to hyaluronic acid)on human bone marrow endothelial cell line(HBME-1). Methods In order to examine the suppressing effects of HyPE on HBME-1 proliferation, migration, and capillary-like tube formation, HBME-1 were activated by angiogenic factor, specifically by basic fibroblast growth factor(b-FGF), vascular endothelial growth factor(VEGF),and oncostatin M(OSM)(at a final concentration of 25, 20, and 2.5 ng/mL, respectively), then HBME-1 proliferation, migration, and tube forma-tion were studied in the absence or presence of HyPE. HBME-1 tube formation was specially analyzed in fibrin gel. Results HyPE effectively inhibited HBME-1 proliferation and migration as a dose-dependent manner, whatever HBME-1 were grown in the control culture medium or stimulated with b-FGF, VEGF, or OSM. In fibrin, the formations of HBME-1 derived tube-like structures were enhanced by all angiogenic factors, but these were strongly suppressed by HyPE. Conclusions The results support the involvement of sPLA2 in angiogenesis. It is proposed that sPLA2 inhibitor introduces a novel approach in the control of cancer development.

Changes of gastric and intestinal blood flow, serum phospholipase A_2 and interleukin-1β in rats with acute necrotizing pancreatitis

AIM:To explore the relationship between gastric and intestinal microcirculatory impairment and inflammatory mediators released in rats with acute necrotizing pancreatitis (ANP). METHODS: A total of 64 rats were randomized into control group and ANP group. ANP model was induced by injection of 5% sodium taurocholate under the pancreatic membrane. Radioactive biomicrosphere technique was used to measure the gastric and intestinal tissue blood flow at 2 and 12 h after the induction of ANP, meanwhile serum phospholipase A2 (PLA2) activities and interleukin-1β levels were determined. Pathologic changes in pancreas, gastric and intestinal mucosae were studied. RESULTS: The gastric blood flow in ANP group (0.62±0.06 and 0.35±0.05) mL/(min·g) was significantly lower than that in control group (0.86±0.11 and 0.85±0.06) mL/(min·g) (P<0.01) at 2 and 12 h after induction of ANP. The intestinal blood flow in ANP group (0.80±0.07 and 0.50±0.06) mlV(min·g) was significantly lower than that in control group (1.56±0.18 and 1.61±0.11) mL/(min·g) (P<0.01). Serum PLA2 activities (94.29±9.96 and 103.71± 14.40) U/L and IL-1β levels (0.78±0.13 and 0.83±0.20)μg/L in ANP group were higher than those in control group (65.27±10.52 and 66.63±9.81) U/L, (0.32±0.06 and 0.33±0.07)μg/L (P<0.01). At 2 and 12 h after introduction of the model, typical pathologic changes were found in ANP. Compared with control group, the gastric and intestinal mucosal pathologic changes were aggravated significantly (P<0.01) at 12 h after induction of ANP. Gastric and intestinal mucosal necrosis, multiple ulcer and hemorrhage occurred. CONCLUSION: Decrease of gastric and intestinal blood flow and increase of inflammatory mediators occur simultaneously early in ANP, both of them are important pathogenic factors for gastric and intestinal mucosal injury in ANP.

Bromophenacyl bromide,a phospholipase A_2 inhibitor attenuates chemically induced gastroduodenal ulcers in rats

AIM: To study the effect of bromophenacyl bromide (BPB), a phospholipase A2 inhibitor on gastric secretion and to protect chemically induced gastric and duodenal ulcers in rats. METHODS: Acid secretion studies were undertaken in pylorus-ligated rats with BPB treatment (0, 5, 15 and 45 mg/kg). Gastric and duodenal lesions in the rats were induced by ethanol and cysteamine respectively. The levels of gastric wall mucus, nonprotein sulfhydryls (NP- SH) and myeloperoxidase (MPO) were also measured in the glandular stomach of rats following ethanol induced gastric lesions. RESULTS: BPB produced a dose-dependent inhibition of gastric acid secretion and acidity in rats. Pretreatment with BPB significantly attenuated the formation of etha- nol induced gastric lesion. BPB also protected intestinal mucosa against cysteamine-induced duodenal ulcers. The antiulcer activity of BPB was associated with signifi- cant inhibition of ethanol-induced depletion of gastric wall mucus, NP-SH and MPO. These findings pointed towards the mediation of sulfhydryls in BPB induced gas- trointestinal cytoprotection. CONCLUSION: BPB possesses significant antiulcer and cytoprotective activity against experimentally induced gastroduodenal lesions.

磷脂酶A_2氨基末端衍生肽的合成及其抗细菌活性的研究

目的 探讨磷脂酶A_(2)(PLA_(2))氨基末端衍生肽的合成及抗菌活性。方法 根据PLA_(2)氨基末端氨基酸残基的顺序合成为多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20),将其分别与2种细菌(大肠埃希菌、枯草杆菌)在特定条件下培养,并以生理盐水作为对照,分析抗菌活性。结果 与对照比较,多肽不同作用浓度时PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20)对革兰氏阳性枯草杆菌杀菌活性更强,各多肽间比较,差异有统计学意义(P<0.05);当多肽作用浓度为500μg/ml时,PLA_(2)N_(15)对革兰氏阳性枯草杆菌杀菌活性可达99.8%,高于PLA_(2)N_(11)、PLA_(2)N_(20),及对照(P<0.05)。与对照比较,各多肽不同作用浓度时对大肠埃希菌杀菌活性比较,差异有统计学意义(P<0.05);多肽作用浓度为7.81、125.00、500.00μg/ml时,PLA_(2)N_(15)的杀菌活性均高于PLA_(2)N_(11)和PLA_(2)N_(20),及对照(P<0.05);多肽作用浓度为31.25μg/ml时,PLA_(2)N_(15)的杀菌活性低于PLA_(2)N_(11)的杀菌活性,且高于PLA_(2)N_(20)的杀菌活性(P<0.05)。结论 多肽PLA_(2)N_(11)、PLA_(2)N_(15)、PLA_(2)N_(20)对枯草杆菌、大肠埃希菌有很强的杀菌作用。

Plasma Lysophosphatidylcholine and Phospholipase A2 Activity in Chagas Disease Patients: A Comparative Analysis

Chagas disease (CD) affects 21 countries in the Americas and is caused by the parasite Trypanosoma cruzi. A key molecule involved in CD is lysophosphatidylcholine (LPC), which has been studied in various contexts: in the saliva of insect vectors, during the establishment of infection in the vertebrate host, and for the parasite itself. This lipid can be produced by the action of phospholipases A2 (PLA2), enzymes that catalyze the hydrolysis of phospholipids releasing fatty acids and lysophospholipids, such as LPC. This study investigates LPC levels and PLA2 activities in the plasma of CD patients and compares these levels with those in healthy individuals and patients with idiopathic dilated cardiomyopathy (IDCM). Plasma from 64 CD patients, 54 healthy individuals, and 16 IDCM patients were analyzed. LPC levels and the activity of two types of phospholipase A2: secreted (sPLA2) and lipoprotein-associated (Lp-PLA2) were measured. LPC levels and sPLA2 activity were similar between CD patients and the control groups. However, there were notable differences in LPC levels and sPLA2 activity between subgroups of CD patients and IDCM patients. This study is the first to identify LPC in patients with CD across various stages of the disease. It also offers new insights into the biochemical changes observed in the plasma of patients with IDCM.

Non-crystallographic symmetry of crystal of neutral phospholipase A_2 from Agkistrodon halys Pallas

Agkistrodotoxin, a neutral phospholipase A2 with high presynaptic neurotoxicity from the venom of Agkistrodon halys Pallas, has been crystallized by hanging drop vapor diffusion method. The crystal belongs to P21 space group with the cell dimensions a = 10.836 nm, b=8.486nm, c = 7.082nm, β=109.87$ showing C2 pseu-do-symmetry. Diffraction data to 0. 26 nm resolution have been collected on a Siemens X-200B area detector. C2 pseu-do-symmetry suggests that there exists a non-crystallographic two-fold axis parallel to crystallographic b axis. Self-rotation function calculation with different integrated radius and resolution ranges using the program POLARRFN yields four stable high peaks corresponding to three more non-crystallographic two-fold axis and one special non-crystal-lographic symmetry. The molecules in the asymmetric unit are suggested to be arranged in a manner of "dimer of dimers" by inference.

Regulatory effects of phospholipase A_2 inhibitors on platelet activating factor in endotoxic shock in rabbits

The regulatory effects of phospholipase A2(PLA2) inhibitors, chloroquine and dexamethasone, on the activity of blood PLA2 and its related lipid mediators during endotoxic shock were observed in rabbits. The rabbits were randomized into 4 groups as follows : The normal control (NC) group consisted of 12 rabbits with sham injection . the endotoxic shork (ES) group of 31 rabbits, the chloquine pretreated (CQ) group of 16 rabbits receiving 3 mg/kg of chlorqouine and the dexamethasone-pretreated (DM) group of 10 rabbits receiving 5 mg/kg of dexamethasone. Blood was sampled before and 5 and 30 min, 1 ,3, 5 and 8 h after the administration of endotoxin for the determination of PLA2, platelet activating factor (PAF) , TXB2 and 6-keto-PGF1α. In addrtion, changes of mean arterial pressure (MAP) and respiratory rate (RR) were also carefully recorded. It was found that the activities of PLA2 and PAF and the levels of TXB2 and 6-keto-PGF1α. were significantly increased after the infusion of endotoxin. CQ and DM markedly suppressed the activities of PLA2 and PAF. The inhibition of CQ on TXB2 and 6-keto-PGF1α was greater than that of DM. Besides, CQ and DM could increase the survival rate of the animals from 48% to 75% (CQ group) and 70% (DM group). These findings suggest that PLA2 inhibitors such as CQ and DM can significantly attenuate the formation of shock mediators such as PLA2, PAF, TXB2 and 6-keto-PGF1α, and so improve the prognosis of the victims of endotoxic shock.

高血压患者视网膜病变与血清脂蛋白相关磷脂酶A_2的相关性研究

目的:探讨高血压视网膜病变(HRP)与脂蛋白相关磷脂酶A_2(Lp-PLA_2)的相关性。方法:回顾性分析2021年7月—2022年3月深圳市福田区5个社区康复中心收治的高血压患者400例病历资料,根据疾病类型分为HRP组(n=240)与单纯高血压组(n=160);另选取同期健康体检者100例为对照组。所有入选者接受常规血压检查、谱域光学相干断层扫描检查及血清Lp-PLA_2检查。比较三组及不同血压水平高血压患者血清Lp-PLA_2水平、黄斑区中心凹血流密度、视网膜厚度及中心凹无血管区(FAZ)面积,分析HRP患者血清Lp-PLA_2水平与FAZ面积、收缩压(SBP)、最佳矫正视力(BCVA)、舒张压(DBP)等的相关性。结果:HRP组血清Lp-PLA_2水平高于单纯高血压组、对照组,黄斑区中心凹血流密度、FAZ面积均大于单纯高血压组、对照组,视网膜厚度小于单纯高血压组、对照组,差异有统计学意义(P<0.05);SBP/DBP>140/90 mmHg高血压患者血清Lp-PLA_2水平高于SBP/DBP<120/80 mmHg患者、120/80~140/90 mmHg患者,黄斑区中心凹血流密度、FAZ面积大于SBP/DBP<120/80 mmHg患者、120/80~140/90 mmHg患者,视网膜厚度小于SBP/DBP<120/80 mmHg患者、120/80~140/90 mmHg患者;Pearson分析显示,HRP患者的血清Lp-PLA_2水平与SBP、DBP、Keith-Wagener分级呈正相关(P<0.05),与BCVA呈负相关(P<0.05)。结论:HRP与血清Lp-PLA_2有关,血清Lp-PLA_2水平升高会增加患者HRP风险,通过血清Lp-PLA_2检查能够为HRP的早期筛查与预后评估提供参考。

Functions and mechanisms of cytosolic phospholipase A_(2)in central nervous system trauma

Central nervous system(CNS)trauma,including traumatic brain injury and spinal cord injury,has a high rate of disability and mortality,and effective treatment is currently lacking.Previous studies have revealed that neural inflammation plays a vital role in CNS trauma.As the initial enzyme in neuroinflammation,cytosolic phospholipase A_(2)(cPLA2)can hydrolyze membranous phosphatides at the sn-2 position in a preferential way to release lysophospholipids andω3-polyunsaturated fatty acid dominated by arachidonic acid,thereby inducing secondary injuries.Although there is substantial fresh knowledge pertaining to cPLA2,in-depth comprehension of how cPLA2 participates in CNS trauma and the potential methods to amelio rate the clinical res ults after CNS trauma are still insufficient.The present review summarizes the latest understanding of how cPLA2 participates in CNS trauma,highlighting novel findings pertaining to how cPLA2 activation initiates the potential mechanisms specifically,neuroinflammation,lysosome membrane functions,and autophagy activity,that damage the CNS after trauma.Moreover,we focused on testing a variety of drugs capable of inhibiting cPLA2 or the upstream pathway,and we explored how those agents might be utilized as treatments to improve the results following CNS trauma.This review aimed to effectively understand the mechanism of cPLA2 activation and its role in the pathophysiological processes of CNS trauma and provide clarification and a new referential framework for future research.

Crystal structure determination of basic phospholipase A_2 from venom of Agkistrodon halys pallas by molecular replacement method

Basic phospholipase A2 (BPLA2) from the venom of Agkistrodon halys pallas has a strong ability to hemolyze erythrocytes. The asymmetrical unit of P212121 crystal of BPLA2 contains two molecules. Self-rotation function was used to study the orientation relationship of these two molecules. Cross-rotation and translation functions were then used to determine the orientations and positions of the two molecules in the unit cell. The model building and preliminary structure refinement were carried out. The result shows that the two molecules in the asymmetrical unit of orthorhombic crystal are related by a non-crystallographic 2-fold symmetry axis.

ABO基因第7外显子c.539G>C突变致A_(2)B亚型结果分析

目的:探讨ABO基因第7外显子c.539G>C突变致A_(2)B亚型结果分析。方法:采用试管凝集法检测ABO血型,采用Sanger测序法进行基因测序及序列分析。结果:4例先证者红细胞为A弱B表型,根据血清学特征定义为A_(2)B血型,先证者1、3、4血清中无抗-A_(1)抗体;先证者2血清中存在抗-A_(1)抗体;4例血型基因型为ABO^(*)A2.08/ABO^(*)B.01,测序结果与A102基因序列比对,A208在c.467C>T和c.539G>C位发生突变,导致多肽链P156L和R180P替换。结论:α-1,3-N-乙酰半乳糖胺转移酶基因c.539G>C突变产生A208表型。

中国发生马铃薯晚疫病菌（Phytopthora infestans）A_2交配型

北京，内蒙古、山西和云南省等省区的１０个菌株，在黑麦琼脂培养基和立马豆Ｖ—８琼脂培养基上进行交配型试验，发现其中３个菌株为Ａ２交配型，７个菌株为Ａ１交配型。Ａ２交配型菌株采自内蒙古自治区和山西省。对卵孢子、藏卵器和雄器的形态进行了描述。ｔｅ，ａ＊ｆｆｎ．ＷｈｅｔｈｅｒＡ，ｅｘｉｓｔｓｏｒｎｏｔｉｎＣｈｉｎａｈａｓｎｅｖｅｒｂｅｅｎｓｔｕｄｉｅｄｂｅｆｏｒｅ．Ｉｎ１９９５ｗｅｂｅｇａｎｔｈｅｉｌｌｖｅｓｔｉｇａｔｉｏｎａｎｄｄｉｓｃｏｖｅｒｅｄＡ，ｉｎＣｈｉｎａ＇Ｔｈｅｐｒｅｌｉｍｉｎａｒｙｒｅｓｕｌｔｓｏｆｔｈｅｓｔｕｄｙｗｅｒｅｐｒｅｓｅｎｔａｓｆｏｌｌｏｗ．ＴｈｅｏｂｊｅｃｔｉｖｅｓｏｆｔｈｉｓｓｔｕｄｙｉｓｔｏｆｉｎｄｏｕｔｂｙｓｕｒｖｅｙｗｈｅｔｈｅｒｔｈｅＡ，ｍａｔｉｎｇｔｙｐｅｅｘｉｓｔｓｉｎＣｈｉｎａ，ａｎｄｆｕｒｔｈｅｒｒｅｓｅａｒｃｈｏｎｔｈｅｉｍｍｉｇｒａｔｉｏｎ，ｍｏｖｅｍｅｎｔ，ｒｅａｓｏｎｆｏｒｄｅｖｅｌｏｐｍｅｎｔａｎｄｅｐｉｄｅｍｉｏｌｏｇｙｏｆｔｈｅＡ，ｗｏｕｌｄｂｅｃａｒｒｉｅｄｏｕｔｌａｔｅｒ．１Ｍａｔｅｒｉａｌｓａｎｄｍｅｔｈｏｄｓｌ＇１ＣＯｌｌｅｃｔｉｏｎｏｆｓａｍｐ?

非铅双钙钛矿A_(2)AgIrX_(6)(A=Cs,Rb;X=Cl,Br)光电特性的第一性原理研究

铅基卤化物钙钛矿因其合适的直接带隙值、优异的载流子迁移率和较高的光吸收率而成为广泛应用于光电领域的优秀半导体材料。然而其较差的稳定性和含有有毒元素Pb限制了它在光电领域的应用。因此,寻找无毒高效的钙钛矿材料是当前面临的一个挑战。非铅卤化物双钙钛矿材料由于性能稳定、无毒高效的特点而有望成为光电领域的潜在应用材料。基于密度泛函理论(DFT),系统研究了A_(2)AgIrX_(6)(A=Cs,Rb;X=Cl,Br)双钙钛矿材料的电子结构和光学性质。容忍因子、八面体因子、形成能、分子动力学模拟均表明A_(2)AgIrX_(6)双钙钛矿具有良好的结构稳定性和热力学稳定性,且均为直接带隙半导体(E_(g)=1.73~2.30 eV),在可见光范围内具有良好的光吸收性能,光吸收系数高达10^(5)cm^(-1),可有效提高光电探测器的效率。研究表明,A2AgIrX6是潜在的光探测器和光电存储器的材料,研究结果可为实验上进一步合成具有高载流子迁移率和强光吸收能力的光电探测器材料提供理论指导。

他克莫司联合激素治疗血清抗PLA_2R抗体持续高滴度的难治性特发性膜性肾病

目的评估他克莫司联合激素对血清抗磷脂酶A2受体(PLA2R)抗体持续高滴度的难治性特发性膜性肾病患者的疗效和安全性。方法召集12例2012年6月至2016年6月间在广州市第一人民医院行常规免疫抑制剂(环磷酰胺、霉酚酸酯或环孢素A)联合激素治疗6个月以上无效且血清抗PLA_2R抗体持续高滴度的特发性膜性肾病患者进行一项开放前瞻性研究。这12例患者被分为两组:改用他克莫司联合激素方案随访治疗12个月的他克莫司组和继续原治疗方案或改用其它常规免疫抑制剂治疗方案继续随访治疗6个月的对照组。结果在入组治疗6个月末,他克莫司组患者尿蛋白定量和血清白蛋白等临床指标均较对照组明显改善(P<0.01),e GFR也比对照组高(P<0.05);而对照组依然存在大量蛋白尿和低蛋白血症,且e GFR也较入组前有显著下降(P<0.01)。治疗6个月后,对照组无一例患者血清抗PLA_2R抗体转阴,也无一例达到临床缓解;而他克莫司组有5例(83.3%)患者血清抗PLA_2R抗体转阴,并达到临床缓解,其中2例(33.3%)完全缓解,3例(50%)部分缓解;治疗12个月后他克莫司组更有4例(66.7%)患者完全缓解。结论血清抗PLA_2R抗体持续高滴度水平,可能是部分难治性特发性膜性肾病患者对常规免疫抑制剂治疗无效的原因。他克莫司联合激素方案可能是使此类患者抗体转阴并达到临床缓解的一种有效治疗方法。

细菌感染大鼠血中血小板型磷脂酶A_2 mRNA水平的变化及其cDNA克隆

目的 观察感染大鼠血中血小板型PLA2 mRNA水平的变化 ,研究其基因和氨基酸顺序结构的特征。为开发新的抗菌药物提供依据。方法 用半定量RT PCR方法检测感染大鼠血中PLA2 mRNA ,并对PLA2 cDNA进行克隆和序列分析。结果 大鼠感染细菌后 ,血中血小板型PLA2 mRNA水平迅速明显增加 ,其DNA和氨基酸结构与其他组织来源的PLA2 有高度的同源性。结论 细菌感染可引起大鼠血中PLA2 在基因水平上的迅速反应 ,这可使血小板型PLA2 的生成增加并控制感染。血中克隆出来的PLA2 cDNA与大鼠其他组织来源的PLA2 虽略有不同 。

苦参碱对内毒素致炎大鼠PLA_2活性影响及其抗炎机制研究

目的 研究苦参碱抗炎机制和其抑制磷脂酶 A2 (PL A2 )活性的作用。方法 用 [3H]花生四烯酸掺入大肠杆菌膜为底物检测细胞内外 PL A2 方法 ,测定了苦参碱对内毒素 (L PS)造成的大鼠急性内毒素炎症时血清中分泌型磷脂酶 A2 (s PL A2 )活性和外周血白细胞中胞浆型磷脂酶 A2 (c PL A2 )活性的影响 ,同时用 Fura2 - AM作荧光指示剂检测胞内游离 Ca2 + 浓度的变化 ,并通过大鼠足跖肿胀实验证实苦参碱的抗炎作用。结果 在 L PS介导的急性内毒素血症大鼠 ,30 mg/ m L 的苦参碱 0 .2 m L ip1h对外周血 s PL A2 抑制效果最好 ,抑制率达 (81.9± 1.8) % ,此时胞内 c PL A2 活性抑制率是 (2 8.4± 6 .0 ) % ,而 Ca2 +浓度是 (15 7.10± 2 0 .5 6 ) nmol/ L,比对照升高 15 .3%。足跖肿胀实验亦证明苦参碱对炎症有显著抑制作用。结论 苦参碱是一种具有抗炎作用的新型 PL A2

黄芩甙、川芎嗪对兔感染性脑水肿与磷脂酶A_2的作用

目的探讨黄芩甙（ＢＣ）、川芎嗪（ＴＭＰＺ）、甘露醇（ＭＮ）对兔百日咳菌液（ＰＢ）脑水肿的治疗作用及机理。方法应用兔感染性脑水肿模型，用光导纤维颅连续监测硬膜外颅内压，测定血清及脑脊液（ＣＳＦ）中磷脂酶Ａ２（ＰＬＡ２）活性、脑组织含水量（ＷＣ）、伊文思蓝（ＥＢ）、钠含量及丙二醛（ＭＤＡ）与超氧化物歧化酶（ＳＯＤ）活性，观察黄芩甙、川芎嗪和甘露醇治疗对血清及ＣＳＦ中ＰＬＡ２活性的抑制作用以及与改善脑水肿的关系。结果血清及ＣＳＦ中ＰＬＡ２活性ＢＣ组和ＴＭＰＺ组明显低于ＰＢ组和ＭＮ组。脑组织含水量、伊文思蓝含量与钠含量：ＰＢ组较ＮＳ组明显增高，治疗各组均减少，依次为ＭＮ组＞ＴＭＰＺ组＞ＢＣ组。３个治疗组均能降低ＭＤＡ浓度，提高ＳＯＤ活性和减轻颅内压增高。降颅内压的作用以ＢＣ最佳，依次为ＴＭＰＺ，ＭＮ。结论ＢＣ与ＴＭＰＺ均可抑制ＰＬＡ２活性和脂质过氧化，从而减轻脑水肿与降低颅内高压。

失血性休克再灌注损伤时血浆磷脂酶A_2及其水解产物的变化

目的和方法：采用家兔失血性休克／再灌注（Ｓ／Ｒ）模型，以放射免疫法分析了动物血清中磷脂酶Ａ２及其活性产物血栓素（ＴＸＢ２）、前列环素（ＰＧＩ２）在损伤过程中的变化规律，同时观察了氯喹及其同类化合物磷酸萘酚喹、抗氧化剂黄芪酮对Ｓ／Ｒ损伤后上述ＰＬＡ２活性产物的影响。结果：氯喹可明显降低ＰＬＡ２，使ＴＸＢ２／ＰＧＩ２比值恢复于接近正常；磷酸酚喹和黄芪酮也可明显降低ＰＬＡ２，使ＴＸＢ２／ＰＧＩ２比值显著低于Ｓ／Ｒ损伤组：ＨＣＯ－３和ｔＣＯ２也得以接近于正常水平。结论：Ｓ／Ｒ过程中ＴＸＢ２的增高导致的ＴＸＢ２／ＰＧＩ２比值改变可能对循环有重要影响；氯喹类化合物及环氧化物酶抑制剂可能通过抑制ＰＬＡ２活性及降低ＴＸＢ２／ＰＧＩ２比值。