丙咪嗪抗血小板聚集作用与细胞外Ca_(2+)浓度的关系

目的：观察丙咪嗪抗血小板聚集作用与细胞外Ｃａ２＋浓度的关系。方法：以比浊度法进行血小板聚集实验。结果：丙咪嗪００１～１ｍｍｏｌ／Ｌ浓度明显对抗凝血酶及二磷酸腺苷诱导的人血小板聚集，且其抗血小板聚集作用随着细胞外Ｃａ２＋增加（加入ＣａＣｌ２１ｍｍｏｌ／Ｌ）与降低（加入乙二醇二乙醚二氨四乙酸１ｍｍｏｌ／Ｌ）而呈现减弱和增强现象，与维拉帕米作用相似。结论：丙咪嗪的抗血小板聚集作用可能与抗钙作用有关。     

凝血酶对牛主动脉内皮细胞表达组织因子活性的影响

目的：探讨凝血酶对内皮细胞表达组织因子(TF)活性的作用及其机制。方法：实验材料为第4～8代新生牛主动脉内皮细胞,采用一期凝固法检测细胞冻融液中的TF活性。结果及讨论：凝血酶可促进血管内皮细胞表达TF活性;凝血酶对内皮细胞的这种刺激作用可能具有Ca^2 ／CaM依赖性,且可能与细胞内cAMP浓度有关。     

EFFECT OF 764－3 ON AGGREGATION AND CALCIUM MOVEMENTS IN AEQUORIN－LOADED HUMAN PLATELETS

ＥＦＦＥＣＴＯＦ７６４－３ＯＮＡＧＧＲＥＧＡＴＩＯＮＡＮＤＣＡＬＣＩＵＭＭＯＶＥＭＥＮＴＳＩＮＡＥＱＵＯＲＩＮ－ＬＯＡＤＥＤＨＵＭＡＮＰＬＡＴＥＬＥＴＳＷｕＨｕａｉｚｈｕ武怀珠；ＬｉＪｉａｚｅｎｇ李家增；ＰｅｎｇＬｉｎ彭林；ＴｅｎｇＢｉｎ滕彬ａｎｄＺ...     

激光扫描共聚焦显微镜观察血小板内钙离子浓度的变化

观察血小板内钙离子浓度的变化及细胞外钙离子对其影响，为探讨血小板内Ｃａ＋＋与疾病的关系及阐明药物作用机制提供理论依据。方法用不同浓度的二磷酸腺苷（ＡＤＰ）、５－羟色胺（５－ＨＴ）、花生四烯酸、瑞斯托霉素、胶原、凝血酶诱导血小板，通过激光扫描共聚焦显微镜观察标记了Ｆｌｕｏ－３的单个血小板内钙离子变化，以及细胞外钙离子对其影响。结果（１）除凝血酶外，其余诱导剂均可引起血小板钙离子浓度变化，且随着诱导剂浓度增加，钙波动频率增加，持续时间延长；（２）ＡＤＰ引起的血小板钙波动，在细胞外无钙离子时，只是幅度减少，而无频率变化；（３）５－ＨＴ引起的钙波动，在细胞外无钙时，波动消失。结论（１）ＡＤＰ、５－ＨＴ、花生四烯酸、瑞斯托霉素、胶原可引起血小板产生钙浓度变化。（２）不同诱导剂诱发的钙波动，其钙离子来源不同。     

花椒油素对A23187和钙调节血小板及细胞内游离钙作用的研究

目的 研究花椒油素对CaCl2和钙离子载体A23187调节血小板及其中Ca2+浓度的作用。方法 比浊法测定血小板聚集，用Fura-2/AM荧光法测定细胞内游离钙的水平。结果 花椒油素显著地抑制CaCl2和A23187诱导的血小板聚集，前者的抑制率为9.0%(67.1%，后者的抑制率为18.1%(72.5%。明显降低A23187诱导的血小板胞质游离Ca2+浓度，降低率为12.8%(63.4%。结论 花椒油素抑制聚集作用与降低细胞内游离Ca2+水平之间呈线性正相关（P<0.01）。     

丙咪嗪对人血小板胞浆游离钙的影响

目的：观察丙咪嗪体外对人血小板胞浆游离钙的影响。方法：用Ｆｕｒａ２－ＡＭ荧光钙离子指示剂在体外测定人血小板胞浆游离钙离子浓度。结果：丙咪嗪明显抑制凝血酶诱导的血小板胞浆游离钙的升高，ＩＣ５０（ｉｎｈｉｂｉｔｏｒｙｃｏｎｃｅｎｔｒａｔｉｏｎｏｆ５０％）为２０．０μｍｏｌ／Ｌ。丙咪嗪对凝血酶诱导的内钙释放亦有明显抑制作用（Ｐ＜０．０１）。结论：丙咪嗪不仅明显抑制人血小板胞外Ｃａ２＋跨膜内流而且抑制胞内储存Ｃａ２＋释放     

莪术二酮抑制凝血酶诱导血小板活化和聚集的研究

目的 研究莪术二酮对凝血酶诱导大鼠血小板活化和聚集的影响,来阐明莪术二酮抗血小板活化的机制.方法 电阻抗法测定凝血酶诱导大鼠洗涤血小板聚集率,计算莪术二酮对其抑制率.荧光分光光度法测莪术二酮抑制血小板胞内钙离子浓度变化.流式细胞术检测血小板P-selectin(CD62p)的表达.Western blot测定磷酸化蛋白的磷酯酶C(PLC)、蛋白激酶C(PKC)和丝裂原活化蛋白激酶(MAPKs)的变化.结果 400 μmol/L的莪术二酮可以有效地抑制0.3 U/ml凝血酶诱导的大鼠血小板的聚集.50、100 μmol/L的莪术二酮可以显著抑制血小板活化标志物[Ca2+]i上升和P-selectin(CD62p)的表达.在蛋白水平上,莪术二酮可以抑制PLCβ3、PKCθ和MAPKs蛋白的磷酸化.结论 初步认为莪术二酮通过PLC-PKC-MAPKs通路抑制凝血酶诱导的血小板活化和聚集,阐明了莪术二酮抗血小板活化的部分机制.     

糖尿病合并微血管病变患者血小板聚集、血栓烷B_2生成与cAMP含量关系的初步探讨

本文对40例糖尿病患者的血小板聚集、血栓烷B_2生成和cAMP含量进行测定并探讨其与微血管病变的关系。结果表明:糖尿病患者血小板聚集增强、血栓烷B_2生成增加,血小板cAMP含量降低。上述改变在无合并微血管病变组已存在,参与微血管病变的发生和发展。血小板血栓烷B_2生成增加可能与血小板膜磷脂酶活性有关。     

α2巨球蛋白抑制蕲蛇毒激活兔血小板的实验观察

An in vitro study of alpha 2-mengaloglobulin (alpha 2MG) in the inhibition of the activation of washed rabbit platelet by Chinese Agkistrodon acutus venom (CAAV) was reported. Results showed that CAAV induced aggregation rate of washed rabbit platelet was positively related to the CAAV concentration, and the maximal aggregation rate was 43.8 +/- 9.9% at the concentration of 100 micrograms/ml. Meanwhile the release of serotonin (5-HT) and platelet factor 4(PF4) from the platelet reached maximum at the CAAV concentrations of 0.81 +/- 0.07 microgram/ml and 39.08 +/- 2.78%, respectively. Platelet aggregation and the release of 5-HT and PF4 induced by CAAV could be inhibited by the addition of 0.25% alpha 2 MG into the platelets both 1 minute before and 1 minute after the addition of CAAV. When alpha 2 MG was added to the platelets 1 minute prior to the addition of CAAV, the platelet aggregation and the ultrastructural changes which could be induced by CAAV were not observed, and the morphology of the rabbit platelets was the same as that of the normal counterparts.     

血浆钙离子浓度对血小板聚集的影响

目的 探讨血浆钙离子浓度对血小板聚集检验结果的影响.方法 采集健康志愿者静脉血标本(n=42),添加不同量的氯化钙,采用血浆比浊法进行血小板聚集率检测.结果 血浆Ca2+浓度在2.1-0.12mmol/l时,二磷酸腺苷(ADP)和花生四烯酸(AA)诱导的血小板聚集率分别为(75.9±10.4)％-(51.8±9.6)％和(83.7±13.9)％-(64.4±12.2)％,血小板聚集率随Ca2+浓度的降低而降低;血浆Ca2+浓度在2.1-33.66mmol/L时,ADP和AA诱导的血小板聚集率分别为(75.9±10.4)％-(94.7士4.8)％和(83.7士13.9)％-(93.2±5.5)％,随Ca2+浓度的增高而增高;Ca2+浓度为39.00mml/L时,血小板聚集率明显降低[ADP和AA诱导的血小板聚集率分别为(9.1±5.3)％和(11.1±4.5)％,均P＜0.01].结论 钙离子浓度波动对血小板聚集检验结果有明显影响.低于生理钙浓度(2.1mmol/L血小板聚集率随Ca2+浓度的降低而降低,高于生理钙浓度血小板聚集率随Ca2+浓度的增高而增高;血钙过高(≥39.0mmol/L)抑制血小板聚集.     

凝血酶对牛主动脉内皮细胞表达组织因子活性的影响

目的 :探讨凝血酶对内皮细胞表达组织因子 (TF)活性的作用及其机制。方法 :实验材料为第 4～ 8代新生牛主动脉内皮细胞 ,采用一期凝固法检测细胞冻融液中的TF活性。结果及讨论 :凝血酶可促进血管内皮细胞表达TF活性 ;凝血酶对内皮细胞的这种刺激作用可能具有Ca2 + /CaM依赖性 ,且可能与细胞内cAMP浓度有关。     

中国蕲蛇酶对血小板功能影响的探讨

The effects of the activation and influence of CAAE on washed human platelets were investigated. Our findings were: (1) CAAE could induce aggregation and alpha-granule release reaction in the washed human platelet suspension; thus it could activate the platelets; (2) the aggregation effect of CAAE was inhibited by albumin and affected by Ca2+, Mg2+ concentration; (3) heparin and/or AT III did not inhibit the aggregation activation of CAAE, but alpha 2MG markedly inhibited it; (4) the aggregation activity of CAAE was associated with the serine protease activity. The mechanism of CAAE-induced aggregation mainly follows the prostaglandins-endoperoxides thromboxane A2 pathway.     

阿司匹林抑制急性心肌梗死患者血小板与白细胞的粘附

目的　研究阿司匹林（乙酰水杨酸,ＡＳＡ）对急性心肌梗死（ＡＭＩ）患者血小板与白细胞粘附的影响及其作用机制。方法　采用体外玫瑰花结形成实验检测血小板与白细胞粘附,观察ＡＳＡ 对两者粘附的作用;用１２５Ｉ标记的单克隆抗体测定血小板表面α颗粒膜蛋白１４０（ＧＭＰ１４０）的表达,观察ＡＳＡ对凝血酶诱导的血小板表面ＧＭＰ１４０ 表达的影响。结果　ＡＭＩ患者血小板与白细胞间粘附率增高,凝血酶通过诱导血小板表面ＧＭＰ１４０ 的表达促进血小板与白细胞粘附;阿司匹林（５００、５ ０００μｇ／ｍ ｌ）抑制ＡＭＩ患者血小板与白细胞间的粘附,抑制凝血酶诱导的正常人血小板与白细胞间的粘附以及凝血酶诱导的血小板表面ＧＭＰ１４０ 的表达。结论　ＡＳＡ一方面通过抑制ＧＭＰ１４０ 的表达,另一方面可能通过影响配体间的结合抑制血小板与白细胞之间的粘附,揭示了ＡＳＡ 抗栓作用的另外一种机制     

血小板活力与胞外钙离子浓度的关系

作者对血小板活力与胞外Ca~(2+)浓度间的关系作了观察。证明在家兔和大鼠的柠檬酸盐抗凝的富含血小板血浆中,以不同的激活剂激活血小板时,其变形速率不因外加不同剂量的Ca~(2+)有所改变;而释放和聚集活力则随外加Ca~(2+)的剂量增加而增加。因此在动物试验中,在其富含血小板血浆中,外加一定量的Ca~(2+)以使血小板活力充分发挥很有必要,以满足当时血小板赖钙反应的进行。     

Effect of Aqueous Extracts of Several Kinds of Herbs on Human Platelet Aggregation and Expression of P-Selectin in Vitro

Objective: To study the effect of aqueous extract of several kinds of herbs on human platelet aggregation and expression of P-selectin in vitro. Methods: Blood was collected from volunteers. Effects of the prepared water extracts of herbs on platelet aggregation were monitored on a Packs-4 aggregometer. The fluorescence intensity of water extracts of Caulis Spatholobi, Flos Carthami and Rhizoma Curcumae on the expression of P-selectin in human platelets of healthy persons was measured with flow cytometry. Results: Out of several herbs investigated, Flos Carthami and Rhizoma Curcumae potently inhibited platelet aggregation after incubation with platelet-rich plasma (PRP) for 15 min. Caulis Spatholobi, Flos Carthami and Rhizoma Curcumae inhibited adenosine-5''-diphosphate (ADP) or platelet activating factor (PAF)-induced platelet aggregation in PRP in a dose-dependent manner. In contrast to Flos Carthami and Rhizoma Curcumae, Caulis Spatholobi could not inhibit thrombin-induced platelet aggregation. Despite its inability to inhibit thrombin-induced platelet aggregation in PRP, Caulis Spatholobi had a greater anti-aggregating activity in PRP induced by ADP or PAF. Caulis Spatholobi and Flos Carthami showed significant inhibitory effects on the expression of P-selectin. Conclusions: Caulis Spatholobi, Flos Carthami and Rhizoma Curcumae have potent anti-platelet properties, and their inhibitory actions are mediated via different mechanisms. Caulis Spatholobi inhibited ADP-induced platelet aggregation but not by thrombin, indicating that its mechanism of action might be independent of the thromboxane pathway. The effect of Caulis Spatholobi and Flos Carthami were associated with suppressing the expression of P-selectin.     

铝对血小板的抗聚及解聚作用

我们发现Al+~3是一种抗血小板物质。实验证明Al~3+对ADP、花生四烯酸或胶原诱发的血小板聚集均有抑制作用,同时对前两者诱发的血小板聚集团也有解聚作用。这些作用均与外加的Ca~(2+)/AP~3+浓度比值有关,提示Al~3+的抗血小板作用是与Ca~(2+)竞争血小板的有关赖钙反应;而以胶原诱发形成的血小板聚集团,则Al~3+无解聚作用。本实验结果在临床上可解释铝中毒时胃肠道的出血症状;在理论上进一步支持血小板间桥分为可逆的与不可逆的两种类型。     

毛葡萄叶水提物抑制血小板聚集的初步研究

目的探讨毛葡萄叶水提物（Gx）对血小板聚集的影响。方法分离健康人的血小板,与不同生药浓度的Gx于37℃孵育10 min后,检测胶原（collagen）和凝血酶（thrombin）诱导的人血小板聚集的变化。小鼠腹腔注射Gx后,分离小鼠血小板,检测二磷酸腺苷（ADP）诱导的血小板聚集的变化。结果 Gx对2μg/ml collagen诱导的血小板聚集有显著抑制作用（P〈0.05）,且呈现Gx的剂量依赖性（P〈0.05）;只有0.01 mg/ml的Gx对0.1 U/mlthrombin诱导的血小板聚集有抑制作用,且不呈现Gx的剂量依赖性。同时,Gx可抑制ADP诱导的腹腔注射Gx的小鼠血小板聚集,且呈现ADP剂量依赖性。结论 Gx具有明显抗血小板聚集作用,为开发抗血栓药物提供了实验依据。     

Specific inhibiting effects of Ilexonin A on von Willebrand factor-dependent platelet aggregation under high shear rate

Background Ilexonin A (IA), purified from the Chinese herbal medicine Maodongqing (Ilex pubescens Hook, et Arn) has been commonly used in south China to treat thrombotic disorders. In this study, we aimed to study the inhibiting effects and mechanism of IA on von Willebrand factor (vWF)-dependent high shear-induced platelet aggregation. Methods vWF-dependent high shear (10800 s-1) induced aggregation of platelets obtained from normal donors in the presence or absence of IA was measured by a modified cone-plate viscometer and shear-induced vWF binding was measured by quantitative flowcytometry with monoclonal antibody known to bind exclusively to the C-terminal domain of vWF (LJ-C3) directly labeled with fluorescein isothiocyanate (FITC). P-selectin surface expression was also measured by a similar method with FITC conjugated anti-P-selectin monoclonal antibody (WGA1). Results Shear-induced platelet aggregation was inhibited by IA in a dose-dependent manner. The extent of aggregation decreased from (78.6±4.6)% in the absence of IA to (36.5±2.1)% in the presence of IA (3.3 mmol/L) (P&lt;0.0001, n=9) with a high shear rate of 10800 s-1. vWF binding and P-selectin expression were also inhibited by IA in a dose dependent manner. The number of binding FITC-LJ-C3 molecules increased after exposure of platelet-rich plasma to a high shear rate of 10800 s-1 for 6 minutes, but this shear-induced increased binding platelet surface vWF molecules and P-selectin expression can be decreased in the presence of IA.Conclusion vWF binding and vWF mediated platelet activation, aggregation occurring under high shear rate were inhibited by IA. IA may be a unique antithrombotic drug inhibiting the vWF-GP Ibα interaction, and may thus facilitate drug design targeting arterial thrombosis.     

普鲁卡因胺抑制凝血酶诱导的人单个血小板游离Ca~(2+)升高

用570型粘附式细胞仪动态观察普鲁卡因胺（Procainamide，Pro）对凝血酶激活的人单个血小板细胞内游离Ca2+的影响。静息状态时对照组和给药组荧光值均较低。当加入0．1u／ml凝血酶时，荧光强度迅速上升，两组达峰值时间均为20s，但给药组最大升高幅度比对照组低21％（P＜0．05）。随后荧光强度迅速下降，两组下降率均为-1u／s，对照组和给药组下降幅度分别为57％和76％（P＜0．05）。上文结果提示，普鲁卡因胺降低凝血酶诱导的血小板游离Ca2+升高，对Ca2+的再摄取没有影响。     

PKC介导凝血酶诱导人肺成纤维细胞单核细胞趋化蛋白-1的表达

摘要：目的研究蛋白激酶C（PKC）在凝血酶诱导人肺成纤维细胞(HLF-1)单核细胞趋化蛋白-1(MCP-1)表达信号通路中的作
用。方法分别用几种不同类型的PKC抑制剂预处理HLF-1,再用凝血酶（10 nmol/L）刺激HLF-1,利用ELISA法检测上清液中
MCP-1的蛋白表达;提取细胞裂解液中总RNA并逆转录合成cDNA,利用实时荧光定量PCR检测MCP-1 mRNA表达水平。结
果广谱型PKC抑制剂Bisindolylmaleimide I 和RO-31-8220 可抑制凝血酶诱导的HLF-1 MCP-1 蛋白释放及mRNA表达,而
Ca2+依赖性PKC抑制剂Gö 6976则没有抑制效果。结论非Ca2+依赖性PKC介导凝血酶诱导HLF-1释放MCP-1。