A nonpeptide vasopressin V(1a) receptor antagonist, SR 49059, does not prevent cisplatin-induced emesis in piglets

We determined the pharmacological and the antiemetic properties of SR 49059, a selective nonpeptide V(1a) receptor antagonist, on cisplatin-induced emesis in the piglet. Firstly, we clearly demonstrate that SR 49059 is a potent V(1a) receptor antagonist in vitro and in vivo in the piglet. In binding studies, [3H]-SR 49059 exhibited high affinity for V(1a) receptors in piglet liver membranes (K(d) of 0.76 +/- 0.12 nM and B(max) of 138 +/- 22 fmol/mg prot.). In vivo, in decerebrate piglets, SR 49059 (1 mg/kg iv) antagonized AVP (500 ng/kg iv)-induced hypertension for at least 150 min and also blocked, for at least 270 min at 3 mg/kg iv, the pressor responses to exogenous LVP. After single and repeated iv or icv administration, we studied the antiemetic properties of SR 49059 on cisplatin-induced emesis in piglets. Animals receiving an emetic dose of cisplatin (5.5 mg/kg, iv) were observed continuously for 60 h. Piglets acting as controls were iv administered with vehicle 15 min prior to cisplatin infusion (T0(-15min)), while experimental animals received a single iv administration of SR 49059 at the dose of 1 or 3 mg/kg. In additional piglets, we administered SR 49059 (3 mg/kg) every 12 h from T0(-15min) to T48(-15min) (cumulative dose, 15 mg/kg). Another set of animals - observed only during the acute phase - was administered with SR 49059 (10 mg/kg) every 3 h from T0(-15min) to T15(-15min) (cumulative dose, 60 mg/kg). Lastly, 10 piglets were given a bilateral icv injection of SR 49059 (500 microg and 1500 microg/side) 1 h prior to cisplatin infusion. In all groups treated with SR 49059, the latency of the first emetic episode and the incidence of vomiting during the acute, the delayed and the cumulative phases remained statistically similar to that observed in controls, suggesting that V(1a) receptors are not involved in the onset and completion of nausea and vomiting.     

Influence of a selective 5HT1-receptor agonist GR43175 on platelet responsiveness

The possible interaction of sumatriptan, a selective 5HT₁-receptor agonist, with platelet responsiveness has been investigated. Stimulation of platelet rich plasma with sumatriptan (1–100 μM) did not induce shape change, aggregation or modification of intraplatelet cytosolic calcium levels. Total inhibition of aggregation induced by 20 μM 5HT was observed in platelets preincubated for 20 min with 100 μM sumatriptan. In the same model, platelet stimulation with 4 μM adenosine 5'-diphosphate (ADP), concentration known to induce an irreversible single-phase curve, determined a decrease of aggregatory response. Concentrations from I μM to 50 μM of sumatriptan did not influence the aggregatory response induced by 5HT and ADP. These effects appear not to be determined by modifications of platelet calcium homeostasis. The possibility to modulate platelet responsiveness by sumatriptan offers a further approach for evaluating the probable link between platelet behaviour and pathophysiology of migraine.     

精氨酸加压素在应激性体温过高中的作用

目的：探讨精氨酸加压素（AVP）是否具有降低应激性体温过高的作用。方法：用无线遥测技术测量大鼠的体温变化,观察腹腔注射AVP和精氨酸加压素V1受体阻断剂（AVP V1阻断剂）对大鼠应激性体温过高的影响。结果：腹腔注射AVP能明显降低大鼠应激性体温过高,而注射AVP V1阻断剂则能提高应激性体温过高的反应。结论：AVP不仅有降低大鼠应激性体温过高的作用,而且证明内源性AVP在应激性体温过高中有负调节作用。     

DENND1B基因多态性与儿童哮喘关系的研究

目的探讨DENND1B基因多态性在儿童哮喘患者中的分布及其与患者血清IgE水平的关系。方法选取哮喘儿童296例(哮喘组),同期健康体检儿童225例(健康对照组),同时提取外周血基因组DNA,通过高温连接酶检测法(PCR-LDR)检测DENND1B基因rs1747815、rs1775444、rs1775456位点的基因型。采用免疫散射比浊法检测样本血清总IgE水平。结果 rs1747815位点3组基因型(GG/GA/AA)及rs1775456位点3组基因型(AA/GA/GG)在健康对照组与哮喘组分布频率差异无统计学意义(P>0.05)。rs1775444位点3组基因型(CC/TC/TT)在健康对照组与哮喘组分布频率差异有统计学意义(P<0.05),其中,哮喘组3种基因型患者中血清IgE水平差异均无统计学意义(P>0.05)。结论 DENND1B基因多态性与儿童哮喘有一定相关性,但与哮喘患者血清IgE水平无相关性。     

Cnb1基因多态性与2型糖尿病相关性研究

目的:研究Cnb1基因的单核苷酸多态性(SNPs)在上海地区人群2型糖尿病(2-DM)患者和正常对照组人群中的基因型频率、等位基因频率分布及其与2-DM的相关性。方法:选取上海地区无亲缘关系的2-DM患者447例及正常对照440名。用稳态模式胰岛素抵抗指数(HOMA-R)及胰岛β细胞功能指数(HOMA-β)估测外周组织胰岛素敏感度及胰岛β细胞功能。采用等位基因专一性实时PCR技术,对2-DM患者及正常对照组人群Cnb1基因的5个SNP位点rs12329083、rs12465425、rs13029910、rs2861814及rs11692815进行基因分型;并进行统计学分析,研究这些位点与2-DM的相关性。结果:rs13029910的CC基因型频率在2-DM患者组中的含量较对照组显著升高(2.7%比0.7%,P=0.021),CC基因型个体2-DM发病风险增高,Logistic回归分析显示,其OR值(比值比)为4.266(P=0.035)。rs12329083(A/T)、rs12465425(G/T)、rs2861814(C/T)及rs11692815(A/G)位点的基因型频率、等位基因频率在2-DM组与正常对照组中的分布差异均无统计学意义(P>0.05)。结论:Cnb1基因可能与上海地区人群2-DM的遗传易感性有关,其中rs13029910多态性位点的基因型CC与2-DM发病风险增高相关。     

宫颈癌患者IL-18基因单核苷酸多态性的筛选

目的 筛选宫颈癌患者IL-18基因单核苷酸多态性位点,初步探讨IL-18基因单核苷酸多态性与宫颈癌相关性,为后续选择合适的单核苷酸多态性标志进行宫颈癌风险预测提供参考.方法 常规方法对原发性宫颈癌患者和健康人群46例进行外周血单个核细胞DNA抽提;自行设计引物,对IL-18基因5′端和6个外显子(长约5 kb)进行PCR法,产物采用DNA测序方法进行分析.结果 在IL-18基因5′端2 kp和6个外显子区域内共筛查出7个候选单核苷酸多态性,频率约0.14%,其中rs1946518和rs1946519的单核苷酸多态性基因型在宫颈癌和健康人之间差异有统计学意义(P＜0.05),且二者存在连锁关系;另有3个位点rs360719、rs360717和rs360718也存在连锁关系,可能与宫颈癌呈负相关,但差异无统计学意义(P＞0.05);位于E4的rs11547404和1个未登陆的单核苷酸多态性分别在1例患者中检测到.结论 采用小样本对特定人群IL-18基因进行测序可有效地筛选出候选单核苷酸多态性.初步发现宫颈癌与IL-18基因上游调控区rs1946518和rs1946519单核苷酸多态性有一定关系,为后续利用单核苷酸多态性标志进行宫颈癌风险预测提供了研究基础.     

Effects of SR 49059, a non-peptide antagonist of vasopressin V1a receptors, on vasopressin-induced coronary vasoconstriction in conscious rabbits

Summary— The effect of SR 49059, a new potent non-peptide vasopressin (AVP) V_1a receptor antagonist, was investigated on AVP-induced electrocardiogram modifications. A high intravenous dose of AVP (0.5 IU or 1.23 μg/animal) produced an important transient t -wave elevation (from 4.7 ± 0.2 to 8.9 ± 0.7 mm) and heart rate decrease (from 199 ± 5 to 99 ± 6 bpm) in conscious rabbits. The t -wave increase was a significant index of coronary vasoconstriction-induced cardiac ischemia. SR 49059 had potent protective effects in this model both by intravenous (0.125 to 0.5 mg/kg) and oral (2.5 to 10 mg/kg) routes. After a 30-min pre-treatment, SR 49059 showed dose-dependent protection on t -wave elevation and heart rate decrease with ED₅₀'s of 95 (95% CL: 168-22) and 30 (95% CL:54-6) μg/kg iv, respectively. Complete blockade occurred with doses of 2 mg/kg iv and upwards. By the oral route, SR 49059 was rapidly absorbed and a dose of 10 mg/kg displayed a protective effect lasting more than 6 hours on both electrocardiogram parameters. Moreover, SR 49059 exerted a high stereospecific inhibitory effect since its enantiomer was totally inactive at 0.5 mg/kg iv, suggesting that protection occurred by interaction with vascular AVP V_1a receptors. Thus, SR 49059 is the first specific non-peptide V_1a antagonist with long-lasting oral activity on AVP-induced coronary vasoconstriction and bradycardia. With this original profile, SR 49059 could be a promising therapeutical antivasospastic agent for preventing AVP- induced cardiac damage.     

Defective platelet responsiveness to thrombin and protease-activated receptors agonists in a novel case of gray platelet syndrome: correlation between the platelet defect and the α-granule content in the patient and four relatives

BACKGROUND: We report a novel case of gray platelet syndrome (GPS). A 14-year-old boy had bleeding diathesis, mild thrombocytopenia, giant platelets with severe defect of alpha-granule secretory proteins, myelofibrosis and splenomegaly. METHODS AND RESULTS: Platelet function studies showed a marked reduction of aggregation and Ca(2+) mobilization by thrombin, protease-activated receptor 1 (PAR1)-activating peptide (AP) and PAR4-AP, PAR1 expression at 55% of normal levels, and a more than two hundred fold reduction of in vitro whole-blood thromboxane B(2) (TXB(2)) production. Sequencing of coding regions of the PAR1 gene failed to show abnormalities. This patient was initially classified as a sporadic case of GPS, as electron microscopy failed to identify giant platelets and/or alpha-granule deficiency in his relatives. However, further studies on the father and three other relatives showed a relative lack of platelet alpha-granule proteins by immunofluorescence microscopy, a defective platelet response to PAR4-AP, and severely reduced in vitro whole-blood TXB(2) production. On this basis, we suggest that in this family, GPS was transmitted in a dominant fashion with highly variable penetrance. CONCLUSIONS: Our study suggests that current diagnostic criteria fail to identify some patients with a mild GPS phenotype and that such patients might be identified by the methods cited above. It also better characterizes the pathogenesis of defective platelet responses to thrombin, and raises interesting questions on the correlation between abnormal PAR function and the lack of alpha-granule content in GPS.     

ATM基因单核苷酸多态性与食管癌易感性的研究

目的食管癌是世界上最常见的恶性肿瘤之一;毛细血管扩张性共济失调症突变基因(ATM)是导致毛细血管扩张性共济失调症发生的致病基因,与肿瘤的发生密切相关;本研究旨在探讨ATM基因单核苷酸多态性与食管癌发生的相关性。方法收集2009年9月至2010年12月期间江苏省淮安市楚州医院就诊的135例食管癌患者标本以及135例健康体检者作为健康对照组。ATM基因单核苷酸多态性分型检测采用Taqman技术,应用Logistc回归统计分析ATM单核苷酸多态性与食管癌发生的相关性。结果吸烟者食管癌的发生率明显高于不吸烟者,差异有统计学意义(χ2=10.252,P=0.001,P<0.05);有肿瘤家族史者患食管癌的概率明显高于没有肿瘤家族史者,差异有统计学意义(χ2=12.199,P=0.000,P<0.05);在食管癌患者组中,A/A基因型占31.9%,A/G基因型占38.5%,G/G基因型占29.6%;而健康对照组中相应的数值分别为25.9%、48.9%和25.2%。以A/A基因型相比,A/G基因型的OR值为0.798(95%CI:0.418-1.521,P=0.493);G/G基因型的OR值为0.534(95%CI:0.265-1.079,P=0.080)。结论 ATM单核苷酸多态性可能与淮安地区的食管癌有关,为食管癌的保护性因素。     

P2Y12基因C34T和G52T位点多态性与氯吡格雷疗效的相关性研究

目的研究血小板膜受体P2Y12基因C34T和G52T位点多态性与氯吡格雷疗效的相关性。方法选取2011年1月1日至2012年1月1日首都医科大学附属北京天坛医院心内科收治的规律服用氯吡格雷的急性冠状动脉综合征患者84例为研究对象。采用单核苷酸多态性(SNP)分型检测方法检测血小板受体基因C34T和G52T,应用血栓弹力仪测定二磷酸腺苷(ADP)途径诱导的血小板抑制率,观察血小板膜受体P2Y12基因C34T和G52T位点多态性与氯吡格雷疗效的相关性。结果氯吡格雷血小板抑制率达标58例(达标组),未达标26例(未达标组);在C34T基因位点,将所有患者按CC、CT、TT分型,分别为53、31、0例;氯吡格雷血小板抑制率达标组与未达标组基因型分布比较差异无统计学意义(P0.05)。在G52T基因位点,将所有患者按GG、GT、TT分型,分别为64、19、1例;氯吡格雷血小板抑制率达标组与未达标组基因型分布比较差异有统计学意义(P0.05)。结论血小板膜受体P2Y12基因G52T位点多态性,可能是影响患者口服氯吡格雷疗效的重要因素之一,治疗前进行基因检测有利于指导用药,降低心血管事件的发生风险。     

Are vasopressin peripheral V1 receptors involved in the development of malignant hypertension and stroke in SHR-SPs?

Summary— The aim of this study was to determine whether activation of vasopressin (AVP) peripheral V₁ receptors is involved in the development of malignant hypertension, stroke, and end-organ damage in stroke-prone spontaneously hypertensive rats (SHR-SPs). For this purpose, young salt-loaded SHR-SPs were treated orally daily from their 5th to 34th week of age, by a selective AVP V₁ receptor antagonist, SR 49059, used in a dose (30 mg/kg) that achieved complete peripheral V₁ receptor blockade. Untreated SHR-SPs served as controls. SR 49059 slightly and transiently (8th to 10th week of age) limited the rise in blood pressure, but thereafter systolic blood pressure values were similar in the two groups of SHR-SPs. Stroke-related mortality was not significantly different in SR 49059-treated and in control animals (65% vs 65% at 30 weeks, 65% vs 83% at 34 weeks). SR 49059 did not prevent the increases in fluid intake, diuresis and proteinuria seen in controls. Histological examination of the brain, kidneys and heart revealed that the development of fibrinoid necrosis and arterial thickening was not prevented by SR 49059, nor was that of malignant nephroangiosclerosis and of myocardial infarction and fibrosis. These data strongly suggest that AVP peripheral V₁ receptor activation is not involved in the pathological processes that develop in SHR-SPs.     

Age related changes of platelet prostacyclin receptors in humans

Platelet receptors for PGI2 were investigated in eighteen healthy volunteers divided in two classes of age: nine were 18-40 years old and nine were 41-65 years old. PGI2 platelet receptors were found to decrease significantly with age; the young subjects had 106 +/- 16 (mean +/- SD) high affinity receptors/platelet and 3509 +/- 529 low affinity receptors/platelet whereas the old subjects had 86 +/- 14 high affinity receptors/platelet (P less than 0.02) and 2471 +/- 640 low affinity receptors/platelet (P less than 0.005). The cumulated data from all the subjects yielded a significant negative correlation with age (r = -0.71, P less than 0.001 for the high affinity class and r = -0.65, P less than 0.01 for the low affinity class). The affinity of receptor sites for the ligand did not statistically change with aging (P less than 0.30 and P less than 0.90 respectively for high and low affinity receptors).     

HLA区域SNPs的检测及应用

人类白细胞抗原（HLA）是迄今为止发现的最复杂的人类基因系统。HLA区域单核苷酸多态性（SNPs）的分布频率高于人类整个基因组水平。目前可用多种方法检测SNPs,其中基于杂交原理的基因芯片方法极具价值。本文主要对HLA区域SNPs的检测方法及其在基因关联分析、法医学及致病基因的搜寻中的应用等方面进行综述。     

TLR7基因单核苷酸多态性与食管癌易感性的相关性研究

目的本研究旨在探讨toll样受体7基因(TLR7)3'端非编码序列microRNA-1265(miR-1265)结合位点单核苷酸多态性rs72552316与食管癌易感性的关系。方法采用单中心为基础的病例对照研究。在这项研究中,聚合酶链反应(PCR)和直接测序被用于204食管癌病例和200例健康对照TLR7基因分型。rs72552316影响miR-1265对TLR7蛋白表达的调控由免疫组化法检测。结果与携带野生型纯合子AA基因型比较,携带rs72552316的GG基因型个体患食管癌的风险增加(OR=2.180,95%CI=1.152-4.127,P=0.019)。此外,在食管癌组织中检测TLR7的表达,这表明TLR7蛋白水平可能与SNP rs72552316相关。结论 Toll样受体7基因3?端非编码序列miR-1265结合位点单核苷酸多态性rs72552316与食管癌易感性相关。miR-1265/TLR7轴可能在食管癌的发生发展中起重要作用。     

白细胞介素23受体的基因多态性与类风湿关节炎的相关性

目的 探讨白细胞介素23受体(interleukin 23 receptor,IL23R)基因的单核苷酸多态性(single nucleotide polymorphisms,SNPs)与类风湿关节炎(rheumatoid arthritis,RA)易感性之间的关系。方法 采用病例对照研究,以228例RA患者和228例正常对照为研究对象,从Hapmap中国人群数据库中选取IL23R基因的标签SNPs(tag-SNPs)。用基质辅助激光解吸电离飞行时间质谱法(MALDI-TOF MS)对IL23R基因的14个tag-SNPs位点进行基因分型,分析其等位基因分布频率及位点间的交互情况。结果 所检测的14个tag-SNPs中,共有3个位点rs10489628、rs10889675和 rs10889677的基因型频率分布在RA组和对照组之间差异有统计学意义(P<0.05)。各类型的单倍体在两组间的分布差异均无统计意义(P>0.05)。结论 IL23R基因的rs10489628、rs10889675和 rs10889677与RA之间存在相关性。     

雌激素受体基因多态性与高血压关系的研究

目的　了解雌激素受体 (ER)基因多态性在中国汉族人群中的分布及其与原发性高血压 (EH)是否相关。方法　应用聚合酶链反应 (PCR)和限制性片段长度多态性 (RFLP)方法检测 97例EH患者和 118例正常对照者ER基因型 ,结合血脂水平探讨两者间的关系。结果　ER等位基因X、x和P、p频率在高血压组和对照组分别为 0 .2 4 7、0 .75 3、0 .16 9、0 .831;0 .4 0 2、0 .5 98、0 .339、0 .6 6 1。基因型频率分布符合Hardy Weinberg平衡定律。XbaⅠ和PvuⅡsg酶切多态性基因型频率 ,等位基因频率及结合XbaⅠ和PvuⅡ两个酶切多态性分析在组内、组间比较均无显著性差异 (P >0 0 5 ) ,且ER基因型间血脂水平在组内比较无统计学意义 (P >0 0 5 )。结论　在EH人群中存在着ERXbaⅠ和PvuⅡ基因多态性 ,但它们与EH无相关性 (P >0 0 5 ) ,不是EH的遗传易感因子。     

Elevated serum level and gene polymorphisms of TGF-beta1 in gastric cancer

Transforming growth factor (TGF)-beta1, as a candidate tumor marker, is currently of interest. In this study, serum TGF-beta1 levels in gastric cancer (GC) patients and healthy volunteers were measured using enzyme-linked immunosorbent assay (ELISA). In addition, single nucleotide polymorphisms (SNPs) of the TGF-beta1 gene at codon 10 and codon 25 were identified by means of amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and sequence analysis. Our results indicated that serum concentrations of TGF-beta1 in GC patients were significantly higher than those in the control, and positively correlated with tumor mass, invasion, metastasis, and clinical stage. The serum TGF-beta1 levels of patients recovering from radical resection were markedly lower than those before surgery. Meanwhile, no deoxyribonucleic acid (DNA) sequence variation at codon 25 of the TGF-beta1 gene was found and a TGF-beta1 gene polymorphism at codon 10 did not show obvious correlations with either TGF-beta1 expression or clinicopathological parameters of GC. Our evidence suggested that serum concentration of TGF-beta1 might be a novel tumor marker for GC and the polymorphisms of TGF-beta1 gene did not play a role as a determinant of serum TGF-beta1 concentration or as a genetic risk factor in the gastric carcinogenesis and progression.     

Controlled shedding of platelet glycoprotein (GP)VI and GPIb–IX–V by ADAM family metalloproteinases

BACKGROUND: Platelet glycoprotein (GP)VI that binds collagen, and GPIb-IX-V that binds von Willebrand factor, initiate thrombus formation. OBJECTIVES: In this study, we investigated the mechanisms of metalloproteinase-mediated ectodomain shedding that regulate the surface expression of GPVI, GPIbalpha (the major ligand-binding subunit) and GPV (that regulates thrombin-dependent activation via GPIbalpha). METHODS AND RESULTS: Immunoblotting human platelet lysates using affinity-purified antibodies against cytoplasmic domains of GPVI, GPIbalpha or GPV allowed simultaneous analysis of intact and cleaved receptor, and revealed (i) that a significant fraction of GPIbalpha, but not GPVI, exists in a cleaved state on platelets, even when isolated in the presence of metalloproteinase inhibitor (GM6001) or EDTA; (ii) the same-sized membrane-associated fragments of GPVI or GPIbalpha are generated by phorbol-ester (PMA), the mitochondrial-targeting reagent CCCP, the calmodulin inhibitor W7, or the thiol-modifying reagent, N-ethylmaleimide, that directly activates ADAM10/ADAM17; and (iii) GPV is shed by both metalloproteinase- and thrombin-dependent mechanisms, depending on the concentration of thrombin. Based on the predicted cleavage area defined by these studies, ADAM10, but not ADAM17, cleaved a GPVI-based synthetic peptide within the extracellular membrane-proximal sequence (PAR;Q(243)YY) as analyzed by MALDI-TOF-MS. In contrast, ADAM17, but not ADAM10, cleaved within the GPIbalpha-based peptide (LRG;V(465)LQ). Both ADAM10 and ADAM17 cleaved within a GPV-based peptide (AQP;V(494)TT). Metalloproteinase-mediated shedding of GPIbalpha from GPIb-IX-transfected or GPVI-transfected cells induced by W7 or N-ethylmaleimide was inhibited by mutagenesis of sequences identified from peptide analysis. CONCLUSIONS: These findings suggest surface levels of GPVI, GPIbalpha and GPV may be controlled by distinct mechanisms involving ADAM10 and/or ADAM17.