原矛头蝮蛇毒的抗凝作用

目的 研究原矛头蝮蛇毒(PMV)对血液系统的作用。方法 将PMV 0.2 mg·kg^-1一次性尾静脉注射给予SD大鼠。注射后0.5, 1, 3, 6和24 h分别取下腔静脉血,制备抗凝全血、抗凝血浆和富血小板血浆(PRP)。利用血细胞计数板对抗凝全血和PRP进行血小板计数;将抗凝血浆用生理盐水稀释5倍,在412 nm测定血红蛋白含量;采用凝血酶时间(TT)、凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)和纤维蛋白原(FIB)含量测定试剂盒分别测定抗凝血浆的TT, APTT, PT和FIB含量;用发色底物法测定抗凝血浆酶切发色底物S-2251的活性。给昆明小鼠一次性尾静脉注射PMV 0.28 mg·kg^-1,在0.5, 1, 3, 6和24 h测定尾部出血时间。结果 给予PMV 0.2 mg·kg^-1 30 min大鼠抗凝全血血小板计数减少至正常对照组的1/3(P<0.01),PRP中血小板计数减少至正常对照组的1/20(P<0.01),抗凝血浆血红蛋白含量增加约6倍(P<0.01);给予PMV 6 h APTT明显延长(P<0.05),3和6 h TT明显延长(P<0.01),1和3 h PT明显缩短(P<0.01);FIB含量和抗凝血浆酶切发色底物S-2251的活性无明显变化。给予小鼠PMV 0.28 mg·kg^-1 30 min小鼠尾部出血时间达(2341±742)s,较正常对照组小鼠(81±11)s明显延长(P<0.01),1 h逐渐缩短(P<0.01),24 h仍未恢复至正常水平(P<0.05)。结论 PMV具有明显的抗凝作用。     

原矛头蝮蛇毒中一个新颖双链纤溶酶的分离纯化与性质研究

目的从原矛头蝮蛇毒中寻找新型纤溶酶,对其理化性质与生物学活性进行研究,以了解其在蛇伤中的作用与毒性机制,并评估其潜在的应用价值。方法采用蛋白层析技术分离纯化获得目标蛋白,检测其分子量、等电点、肽指纹图谱、多种蛋白水解活性、抗补体活性、出血活性、水肿活性及对流血时间的影响。结果通过阴离子交换层析、凝胶过滤层析、亲和层析从原矛头蝮蛇毒中纯化出一个酸性纤溶酶PMSP-A,它是由两条等电点分别为5.7与6.1的非均等肽链共价结合而成。SDS-PAGE和凝胶过滤测定其分子量分别为26.1 ku与25.3 ku。肽指纹图谱分析表明PMSP-A与黄绿烙铁头蛇毒中的血液凝固结合因子有部分序列吻合。PMSP-A能够依次降解纤维蛋白原的Bβ、Aα链,该活性能被PMSF、1,10-phenanthroline抑制,EDTA、EGTA、SBTI不能抑制其活性。PMSP-A具有纤维蛋白、精氨酸酯水解活性,没有偶氮酪蛋白水解活性。它还具有抗补体活性。动物实验表明,PMSP-A明显延长小鼠尾静脉流血时间,能诱导小鼠足趾轻度水肿,无皮下出血活性。结论 PMSP-A是一个新颖的原矛头蝮蛇毒双链丝氨酸蛋白酶,具有多种影响机体的生物学活性。     

内镜下注射矛头蝮蛇血凝酶治疗消化性溃疡出血的疗效及对血小板参数指标的影响

目的 探究与分析内镜下注射矛头蝮蛇血凝酶治疗消化性溃疡出血的疗效及血小板参数指标的影响.方法 采取随机数表法对自2016年3月～2021年3月收治的消化性溃疡出血患者120例分组,各60例,对照组给予传统方案治疗,观察组给予内镜下注射矛头蝮蛇血凝酶治疗,对比两组临床止血疗效、治疗前后pH值>6持续时间占总时间的百分率、...     

尖吻蝮蛇毒小分子多肽的分离及抗血小板聚集作用

目的从尖吻蝮蛇毒中分离纯化一种抗血小板聚集小分子多肽,研究其理化性质以及对ADP、胶原、凝血酶诱导的血小板聚集反应的影响。方法经SephadexG-75凝胶过滤,超滤,DEAE-SepharoseCL-6B离子交换层析法分离纯化蛇毒组分,采用高效液相鉴定纯度,用SDS-凝胶电泳(SDS-PAGE)测定其分子量,用比浊法测定其抗血小板聚集活性。结果从尖吻蝮蛇毒中分离相对分子质量约为7862u等电点为4.29的组分,该组分能抑制由ADP、胶原、凝血酶诱导的血小板聚集并成剂量依赖性。结论此法成功地从尖吻蝮蛇毒中纯化出抗血小板聚集组分。该组分与去整合素比较相似,可能属于去整合素家族。     

蝮蛇毒血小板抑制因子对动脉血栓形成的影响及机制研究

目的：探讨皖南蝮蛇毒血小板抑制因子（AHV-PI）对家兔动脉血栓形成的影响及可能机制。方法：新西兰家兔24只,随机分成假手术组、动脉血栓模型组、阳性对照组（奥扎格雷钠,5mg/kg）,AHV-PI（0.1mg/kg）实验组共4组,每组6只。应用70%FeCl3溶液化学损伤的方法来制备家兔颈动脉血栓模型,采用血栓弹力仪（TEG）描计血栓弹力图,比浊法测定家兔血小板聚集率,ELISA测定各组血浆中α颗粒膜蛋白（GMP-140）和血栓素B2（TXB2）水平,光镜和透射电镜分别观察动脉血栓形成和血小板形态的改变。结果：AHV-PI实验组与模型组相比,血栓弹力图凝血时间（R）值和血凝块形成时间（K）值延长（P〈0.01和P〈0.05）,Alpha角度、最大幅度（MA）和凝血指数（CI）减小（P〈0.05和P〈0.01）;血小板聚集率的各项指标均明显降低（P〈0.05）;血浆中GMP-140和TXB2含量降低（P〈0.01）。AHV-PI实验组光镜下动脉内未见血栓形成,血小板电镜显示血小板形态基本规则,与模型组相比伪足较少,α-颗粒和致密颗粒无明显减少,胞浆空泡化现象减轻。结论：AHV-PI可以通过抑制血小板聚集,防止动脉血栓的形成,其机制可能与之保护血小板超微结构,减少血小板脂质代谢和颗粒内容物的释放有关。     

蝮蛇抗栓酶对体外血小板聚集的影响

本文比较了不同的浓度蝮蛇抗栓酶(svate)对人血小板聚集的影响。结果表明,不同浓度蝮蛇抗栓酶对试管内血小板聚集均有明显抑制作用,其抑制作用与浓度呈正比。     

蝮蛇毒蛋白C激活物抗凝机制的研究

目的研究蝮蛇毒纯化蛋白C激活物(PCA)的抗凝机制.方法测定PCA对正常人混浆KPTT、PT、TT的影响;对白兔的KPTT、PT、TT和Fgn的影响.结果PCA在0.1 mg@L1时对正常人混浆KPTT可明显延长,但PT和TT不受影响,当它的浓度增到200mg@L,PT也可延长,但TT依然无明显变化;PCA可明显延长白兔的KPTT.结论PCA在低浓度时优先抑制凝血系统第一阶段内凝途径,在高浓度时也妨碍外凝途径或共同途径,具有体内抗凝作用.     

注射用矛头蝮蛇血凝酶的临床应用综合评价

目的:探索注射用矛头蝮蛇血凝酶临床应用的综合评价方法,为今后相关工作的开展和完善提供参考。方法:通过文献检索获取相关文献资料,从有效性、安全性、经济性等方面对注射用矛头蝮蛇血凝酶临床应用进行系统综合评价。结果:注射用矛头蝮蛇血凝酶能缩短平均止血时间,减少出血量,不影响正常的凝血功能,未见严重不良反应;相较于其他血凝酶更具有经济性,但需更多真实世界研究数据对其进行评估。结论:注射用矛头蝮蛇血凝酶临床应用前景好,但需更深入的研究。     

首批矛头蝮蛇血凝酶国家标准品及对照品的研制

目的：建立首批矛头蝮蛇血凝酶国家标准品及对照品。方法：对矛头蝮蛇血凝酶标准品进行了理化分析、效价测定及稳定性考察;对矛头蝮蛇血凝酶对照品进行了结构确证、纯度考察、理化分析及稳定性考察。结果：建立了效价定值为101单位/支的矛头蝮蛇血凝酶标准品用于效价测定;建立了结构准确、纯度较高的矛头蝮蛇血凝酶对照品用于鉴别及检查测定。结论：首批矛头蝮蛇血凝酶国家标准品及对照品的研制规范了相关药品质量,为酶类生化药物的质量研究提供了思路及依据。     

三种蝮蛇抗栓酶注射剂对大鼠和家兔血小板聚集的影响

用比浊法研究三种蝮蛇抗栓酶注射剂对大鼠和家兔血小板聚集的影响,结果表明蝮蛇抗栓酶注射剂在试管内浓度0.045u/ml 时对大鼠和家兔血小板聚集无明显抑制作用。静脉注射蝮蛇抗栓酶注射剂1u/kg 对家兔血小板聚集有明显抑制作用。尤其是蛇岛蝮蛇抗栓酶注射剂抑制作用最为显著。     

Red blood cell aggregation by Trimeresurus mucrosquamatus snake venom.

T. mucrosquamatus venom induced aggregation of rabbit and human RBC's at a concentration higher than 25 μg/ml. This aggregation was inhibited by EDTA and could be reversed by Ca²⁺. α-Methylgalactoside, but not α-methyl-glucoside, competitively inhibited the venom-induced RBC aggregation. Trypsin and neuraminidase pretreatment of RBC did not potentiate this aggregating effect. It was concluded that venom-induced aggregation was due to a lectin-like binding to saccharide (galactosyl)-receptors of the RBC membrane. At a sublethal i.v. dose (1 mg/kg), the venom did not cause significant changes of rabbit RBC counts.     

Effects of Heloderma suspectum venom on blood coagulation

The effect on blood coagulation of venom from the Gila monster Heloderma suspectum was studied in vivo and in vitro. Lethal and sublethal doses of venom failed to alter the clotting and prothrombin times of rabbit and cat blood in vivo. Venom mixed with freshly drawn blood from rabbits and cats had no effect on the clotting time. When venom was incubated with human, rabbit, and cat plasma for periods longer than 5 min, prothrombin time was prolonged. Placing venom in a boiling water bath for 15 min did not alter this.     

Effect of scorpion venom and its fractions on the crayfish stretch receptor organ

The effects of the crude venom of the scorpion Androctonus australis Hector and its insect toxin, mammal toxin II and the ‘crustacean fraction’ were tested on the crayfish stretch receptor organ. The ‘crustacean fraction’ was able to mimic the excitatory and blocking action of the crude venom, while the insect and mammal toxins were inactive. It is suggested that the specificity in the action of the ‘crustacean fraction’ is due to a specific affinity to a crustacean neural system.     

Effects of Loxosceles laeta spider venom on blood coagulation

The hematologic effects of intradermal injection of Loxosceles laeta venom in rabbits were studied with special reference to partial thromboplastin time, prothrombin time, platelet count and fibrinogen-fibrin degradation products. The in vitro effect of Loxesceles laeta venom on human platelet aggregation was also studied. Fibrinogen and platelet count decreased and fibrinogen-fibrin degradation products increased at 12 hr.     

Anaphylactogenic properties of bee venom and its fractions

I have investigated the anaphylactogenicity of whole bee venom and its pure protein and peptide components (phospholipase A, melittin and apamin) and the partially purified protein and peptide fractions (the highest-molecular weight fraction I, hyaluronidase, fractions Op, P₁ and P₂ and protease inhibitor) obtained by means of gel-filtration and ion-exchange chromatography. Anaphylactogenicity was observed with the whole bee venom and the high molecular weight protein fractions—fraction I, phospholipase A and hyaluronidase. The peptides melittin, apamin, fraction Op (mast cell degranulating peptide, MCD) and fractions P₁ and P₂ did not show any anaphylactic properties after sensitization with or without Freund's complete adjuvant.     

The effects of Naja flava venom on blood coagulation

The effects of Naja flava venom on blood coagulation, fibrinogenolysis and fibrinolysis were studied in vitro. No coagulant activity could be detected, but the venom has a definite anticoagulant action. This may be through interference with the generation of thromboplastin and acceleration of its destruction after it is formed, probably because of the phospholipase A activity of the venom. The venom delays and decreases the generation of thrombin probably due to the anti-thromboplastin activity of the venom, but it has no effect on formed thrombin, or the thrombin-fibrinogen reaction. The venom has a direct fibrinogenolytic action but no action on formed fibrin, nor does it activate the intrinsic fibrinolytic system.     

Characterization of snake venom components acting on blood coagulation and platelet function.

Snake venoms can affect blood coagulation and platelet function in various ways. The physicochemical properties and the mechanisms of actions of the snake venom components affecting blood coagulation and platelet function are discussed.