内质网甘露糖甙酶-Ⅰ样蛋白的研究进展

内质网甘露糖苷酶-Ⅰ样蛋白(EDEM)是受内质网应激诱导之后,启动内质网相关糖蛋白降解(GERAD)途径发生的一种有酶结构域但无酶活性的蛋白。现就EDEM编码基因及其蛋白质的结构与功能解析、EDEM参与的GERAD途径,特别是EDEM的作用机制及诱导调控等诸方面予以综述。     

新型α-半乳糖苷酶清除动物红细胞表面αGal抗原的研究

异种抗原αGal是引起异种移植免疫排斥反应的重要原因之一。脆弱类杆菌来源的α-半乳糖苷酶是一种新型的糖苷酶,能够切除支链多糖和直链多糖末端的αGal残基。本研究探讨新型α半乳糖苷酶清除红细胞表面αGal抗原的作用。利用新型的基因重组α-半乳糖苷酶酶解牛、猪、狗、兔红细胞上的异种抗原,并用流式细胞术分析细胞表面的αGal抗原。结果表明,动物红细胞表面的异种抗原αGal被完全或部分清除。结论:新型α-半乳糖苷酶可以用来清除异种红细胞上的αGal抗原,对降低异种移植引起的超急性排斥反应具有潜在意义。     

原核基因工程制备新型重组α-半乳糖苷酶应用于人B→O血型改造的研究

本研究利用基因工程方法制备脆弱类杆菌来源的新型α-半乳糖苷酶并将其应用于人B→O血型改造.在获得了能够表达细菌α-半乳糖苷酶工程菌株的基础上,从诱导时间、诱导剂浓度两个方面对工程菌株的诱导条件进行优化,获得细菌α-半乳糖苷酶的最佳可溶性表达条件;超声上清经过阳离子交换层析和阴离子交换层析等方法进行纯化.利用纯化后的α-半乳糖苷酶在磷酸盐缓冲液(pH 6.8)中处理B型红细胞2小时,制备O型红细胞.结果表明细菌α-半乳糖苷酶最佳诱导表达条件为:37℃、起始D(600)为0.8,IPTG浓度为0.1 mmol/L,诱导时间为2小时.纯化后α-丰乳糖苷酶的纯度为电泳纯,比活由纯化前的0.42 U/mg提高到了2.1 U/mg.该酶在26℃、接近中性的pH条件(6.8)下经2小时可将B型红细胞改造成O型红细胞,需要的酶量为225μg/ml红细胞.结论:建立了重组细菌α-半乳糖苷酶的表达纯化工艺,制备的重组α-半乳糖苷酶可有效地将B型红细胞改造成O型红细胞,为B→O血型改造提供了更有效的工具酶.     

利用新型α-半乳糖苷酶进行B→O血型改造

目的利用原核生物来源的α-半乳糖苷酶进行B→O血型改造研究。方法应用PCR的方法从脆弱类杆菌(Bacteriodes fragilis)中克隆了新型α-半乳糖苷酶基因,构建原核生物表达载体,转化大肠杆菌BL21(DE3),IPTG诱导α-半乳糖苷酶的胞内可溶性表达,应用重组酶的上清液进行B型红细胞(RBC)初步酶解试验。结果重组酶分子量约为64.6 kD,超声破碎的菌液上清中的酶活力约为2 U/ml。在26℃及pH 6.8的等渗柠檬酸-磷酸氢二钠缓冲体系中2,h内完全酶解200μl B型RBC需要30μl的上清液,酶解后的B型RBC与抗-B和抗-A单克隆抗体不凝集,流式细胞术检测结果显示酶解后B型RBC的血型抗原呈现O型特征。结论重组的α-半乳糖苷酶可以有效的将B型RBC转变为O型RBC。     

重组血型改造工具酶稳定性的研究

目的研究血型改造工具酶,重组咖啡豆α-半乳糖苷酶在不同保存条件下的稳定性。方法以酶解B型红细胞的活性和纯度作为主要检测指标,考察重组α-半乳糖苷酶的热稳定性。重组α-半乳糖苷酶在70℃条件下保存1d,37℃保存60d,室温、4、-20、-70℃分别保存6个月,定期取样观察样品的外观,检测样品的pH值、纯度、酶活性,并进行无菌试验;为确保临床使用中的安全性和有效性,我们对4℃保存的样品进行了长达3年的观察。结果重组α-半乳糖苷酶在70℃保存1d后失活,37℃保存2个月后活性降低了11.5%,室温保存6个月后活性降低了19%,-70℃保存6个月后活性降低了13%,4℃、-20℃保存的样品6个月内各项指标均正常,均未见蛋白明显降解,蛋白活性保持稳定。4℃保存3年的样品酶活性保持稳定,可按原剂量在26℃,2h内成功地将B型红细胞改造成O型红细胞。结论重组α-半乳糖苷酶对热不稳定,应保存4℃或-20℃,在此条件下,有效期至少2年,能满足常规临床要求。     

内质网甘露糖甙酶-I样蛋白的研究进展

内质网甘露糖苷酶-I样蛋白（EDEM）是受内质网应激诱导之后，启动内质网相关糖蛋白降解（GERAD）途径发生的一种有酶结构域但无酶活性的蛋白。现就EDEM编码基因及其蛋白质的结构与功能解析、EDEM参与的GERAD途径，特别是EDEM的作用机制及诱导调控等诸方面予以综述。     

α—半乳糖苷酶及其在输血等方面的应用

α－半乳糖苷α－ｇａｌａｃｔｏｓｉｄａｓｅ,α－Ｇａｌ,Ｅ．Ｃ．３．２．１．２２）是广泛存在于自然界中的一种外切糖苷酶,传统上划分为两类异构酶,即α－半乳糖苷酶Ａ和α－半乳糖苷酶Ｂｏ在体内,α－半乳糖苷酶Ａ水解以α－半乳糖残基为末端的糖复合物,而α－半乳糖苷酶Ｂ则水解以α－半乳糖苷酶则水解以α－Ｎ－乙酰－氨基半乳糖残基为末端的聚糖及糖蛋白、糖脂等复合物,因而它实际上是一种α－Ｎ－乙酰－半乳糖胺酶。     

联合应用α-半乳糖苷酶和α-N-乙酰半乳糖胺酶实现红细胞AB→O血型转变

目的研究酶解去除AB型红细胞表面的A和B抗原、实现AB→O血型转变的方法,以获得通用型红细胞。方法联合应用α-半乳糖苷酶和α-N-乙酰半乳糖胺酶酶解AB型红细胞,用单克隆抗-A、抗-A1和抗-B抗体检测酶解效果,用稀有血型抗体检测酶解前后红细胞表面的稀有血型,用流式细胞术检测酶解前后红细胞表面A、B、H抗原,原子力显微镜观察酶解前后红细胞形态,主侧配血试验检测酶解红细胞是否符合临床输血要求。结果A1B和A2B亚型红细胞的A、A1和B抗原均能够完全被酶解去除,酶解前后红细胞的稀有血型抗原不变;流式细胞术显示,酶解后AB型红细胞表面的A和B抗原消失,而H抗原明显增加,和O型红细胞相当;酶解不影响红细胞的形态;主侧配血试验证明酶解改造后的AB型红细胞可以安全输给O、A、B、AB等各型受血者。结论联合应用α-半乳糖苷酶和α-N-乙酰半乳糖胺酶成功实现了AB→O血型转变,获得酶解通用型红细胞。     

尿酶联合尿微量蛋白检测诊断糖尿病肾病

目的探讨应用尿酶联合尿微量蛋白检测来诊断早期糖尿病肾病。方法收集2010年12月至2011年12月68例糖尿病患者和60例健康体检者尿蛋白检测为阴性的晨尿,采用速率法检测N-乙酰-β-D氨基葡萄糖苷酶(NAG)、β-D-半乳糖苷酶(GAL),采用免疫散射比浊法检测尿微量清蛋白(mAlb)、转铁蛋白(TRF)、α1-微球蛋白(α1-MG),jaffe速率法测定肌酐,然后进行统计和分析。结果 (1)糖尿病患者组尿NAG、GAL、mAlb、TRF、α1-MG的水平均明显高于健康对照组(P<0.01);(2)单项检测尿NAG、GAL、mAlb、TRF、α1-MG阳性率较低,联合检测阳性率显著增高,最高达76.4%,而且尿酶与尿微量蛋白呈显著正相关性。结论联合检测尿酶和尿微量蛋白是诊断糖尿病患者肾脏早期损伤的敏感、可靠的指标。     

黄芩苷抗呼吸道合胞病作用的研究

目的研究黄芩苷对呼吸道合胞病毒(RSV)感染的BALB/c小鼠干扰素(IFN)-α及IFN-β表达的干预作用,探讨其抗病毒机制。方法建立BALB/c小鼠呼吸道合胞病毒感染模型,采用酶联免疫吸附试验(ELISA)法检测小鼠肺组织IFN-α及IFN-β的水平。结果黄芩苷能明显增加RSV感染BALB/c小鼠的IFN-α及IFN-β的表达。结论黄芩苷在小鼠体内可以通过调控IFN的表达来发挥抗RSV的作用。     

痰中检测核不均一核糖核蛋白A2/B1早期诊断肺癌的意义

目的：探讨检测痰中核不均一核糖核蛋白A2/B1（heterogeneous nuclear ribonucleoprotein A2/B1,hnRNP A2/B1）在肺癌早期诊断中的意义。方法：收集63例疑诊肺癌患者的痰标本,分别采用痰涂片、痰细胞块切片细胞学检查（镜检找到癌细胞即诊断为肺癌）及痰细胞块切片免疫组织化学检测hnRNP A2/B1（表达阳性即诊断为肺癌）进行诊断,比较2种诊断方法的结果。结果：痰涂片及痰细胞块切片细胞学检查诊断肺癌的敏感度为31.8%,特异度为100%。痰细胞块检测hnRNP A2/B1诊断肺癌的敏感度为80%,特异度为68.4%。检测痰hnRNP A2/B1的敏感度显著高于痰细胞学检查（P〈0.01）。结论：痰细胞块结合免疫组织化学法检测hnRNP A2/B1有助于发现早期肺癌。     

Up-regulation of adhesion molecule expression and induction of TNF-alpha on vascular endothelial cells by antibody against human parvovirus B19 VP1 unique region protein

BACKGROUND: Human parvovirus B19 infection has been frequently described as a cause or trigger of various autoimmune diseases. In previous studies, we have postulated the association among human parvovirus B19 (B19)-VP1 unique region (VP1u), production of anti-beta2-glycoprotein I (anti-beta2GPI) antibody and anti-phospholipid syndrome (APS)-like autoimmunity. However, the precise role of B19-VP1u in induction of APS is still obscure. METHODS: To further elucidate the pathogenic roles of VP1u in B19 infection and autoimmunity, we examined the effect of anti-B19-VP1u IgG antibodies on endothelial cells that is recognized to play crucial roles in APS. Human vascular endothelial cells, ECV-304, were incubated with various preparations of purified human or rabbit IgG. The activation of endothelial cells and production of cytokines were assessed by flow cytometry and ELISA, respectively. RESULTS: Purified IgG from rabbits immunized with recombinant B19-VP1u proteins can up-regulate ICAM-1 (CD54), VCAM-1 (CD106), E-selectin (CD62E), MHC class II (HLA-DR, DP, DQ) molecule expression, and TNF-alpha production in endothelial cells as compared to those endothelial cells cultured with control IgG. Additionally, significantly increased phosphorylated-P38 mitogen-activated protein kinase (P38 MAPK) and iNOS were observed in both human anti-beta2GPI IgG and rabbit anti-B19-VP1u IgG treated-ECV-304 cells, respectively. CONCLUSIONS: These experimental results imply that antibodies against B19-VP1u play important roles in the immunopathological processes as well as human anti-beta2GPI IgG that leads to development of APS by involving p38 phosphorylation and iNOS activation. It could provide a clue in understanding the role of anti-B19-VP1u antibodies in APS manifestations.     

EMILIN1 CYP11B2基因多态性与原发性高血压相关性研究

目的 研究 EMILIN1、CYP11B2基因多态性与原发性高血压的相关性。方法 回顾性分析该院2010年3月至2012年3月期间收治的100例原发性高血压患者,将其作为临床研究对象（患者组）,另选取血压正常的健康自愿者100例作为健康对照组,进行基因多态性的对比研究。采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法 分别检测两组EMILIN1基因SNP位点和CYP11B2基因SNP位点的等位基因及基因型分布情况。结果 患者组患者EMILIN1基因rs2304682位点上的基因型与等位基因频率与健康对照组比较,差异有统计学意义（P＜0．05）,患者组CG基因型、G等位基因频率明显高于健康对照组,而CC基因型、C等位基因频率则比健康对照组低;CYP11B2基因多态性基因型及等位基因频率发现,患者组（CYP11B2）-344 T/C基因多态性中TT基因型、T基因频率明显高于健康对照组,而CT 基因型、C基因频率则低于健康对照组,差异均有统计学意义（P＜0．05）。结论 EMILIN1基因多态性可能与原发性高血压有一定的相关性,（CYP11B2）-344T/C位点上等位基因T的频率较高。     

伴t(1;19)(q23;p13)和E2A-PBX1成人急性T淋巴细胞白血病一例报告附文献复习

目的 总结1例伴有t(1;19)和E2A-PBX1融合基因阳性的成人T细胞急性淋巴细胞白血病(ALL)患者的诊疗体会.方法 对1例成人T细胞ALL患者进行染色体核型分析,流式细胞术检测免疫表型,同时进行融合基因多重RT-PCR扩增.结果 患者染色体核型为47,XY,9p+,15p+,17q-,der(19),t(1;19)(q23;p13)[5]/46,XY[15].E2A-PBX1融合基因阳性表达.给予hyperCVAD(环磷酰胺+长春新碱+阿霉素+地塞米松)方案治疗后患者获血液学完全缓解,染色体核型复查为46,XY[10],E2A-PBX1融合基因检测阴性.结论 E2A-PBX1+ t(1;19)也可以发生于T细胞ALL,E2a-PBX1白血病细胞在不同的癌基因协同信号或微环境下转化方向可变.     

Protein Tyrosine Phosphatase 1B Inhibitors: A Molecular Level Legitimate Approach for the Management of Diabetes Mellitus

Diabetes mellitus is a systemic disease responsible for morbidity in the western world and is gradually becoming prevalent in developing countries too. The prevalence of diabetes is rapidly increasing in industrialized countries and type 2 diabetes accounts for 90% of the disease. Insulin resistance is a major pathophysiological factor in the development of type 2 diabetes, occurring mainly in muscle, adipose tissues, and liver leading to reduced glucose uptake and utilization and increased glucose production. The prevalence and rising incidence of diabetes emphasized the need to explore new molecular targets and strategies to develop novel antihyperglycemic agents. Protein Tyrosine Phosphatase 1B (PTP 1B) has recently emerged as a promising molecular level legitimate therapeutic target in the effective management of type 2 diabetes. PTP 1B, a cytosolic nonreceptor PTPase, has been implicated as a negative regulator of insulin signal transduction. Therefore, PTP 1B inhibitors would increase insulin sensitivity by blocking the PTP 1B‐mediated negative insulin signaling pathway and might be an attractive target for type 2 diabetes mellitus and obesity. With X‐ray crystallography and NMR‐based fragment screening, the binding interactions of several classes of inhibitors have been elucidated, which could help the design of future PTP 1B inhibitors. The drug discovery research in PTP 1B is a challenging area to work with and many pharmaceutical organizations and academic research laboratories are focusing their research toward the development of potential PTP 1B inhibitors which would prove to be a milestone for the management of diabetes. © 2010 Wiley Periodicals, Inc. Med Res Rev, 32, No. 3, 459–517, 2012     

GRIN2B启动子区多态性与散发性阿尔茨海默病关系的功能学分析

目的探讨N-甲基-D-天冬氨酸受体2B(N-methyl-D-aspartate receptor 2B,NR2B)基因GRIN2B启动子区多态性对其转录活性的影响,从功能学方面阐述GRIN2B与散发性阿尔茨海默病(sporadic Alzheimer’s disease,SAD)的关系。方法选取双荧光报告基因系统(pGL3-Basic及pRL-TK)为报告基因载体,用基因重组和定点突变技术构建含不同基因型的GRIN2B启动子报告基因质粒,转染人神经母细胞瘤(SH-SY5Y)细胞和人宫颈癌上皮(HeLa)细胞,计算不同环境下各启动子的相对荧光素酶活性(relative luciferase activity,RLA)。结果在细胞未处理情况下,pGL-TCTG和pGL-GACA两者的RLA没有差异(SH-SY5Y细胞中P=0.149;HeLa细胞中P=0.288),而pGL-TATG的转录活性与pGL-TCTG相比有显著性差异,转录活性约增加1.5-1.7倍(SH-SY5Y细胞中P=0.000;HeLa细胞中P=0.000);所检测的三种GRIN2B启动子质粒在血清剥夺、Na2S2O4、H2O2及Aβ25-35干预下的RLA与非处理组相比均无显著性差异(P0.05)。结论-421C/A碱基的改变,可引起GRIN2B启动子启动活性的改变,-421C型质粒下调了GRIN2B启动子的转录活性。     

脓毒症大鼠肺基质金属蛋白酶-2/9表达与血必净干预

目的 观察创伤弧菌脓毒症大鼠肺基质金属蛋白酶(MMP)-2/9和组织型金属蛋白酶抑制剂(TIMP)-1/2的动态表达及血必净干预.方法 温州医学院生命科学院实验室,清洁级SD大鼠110只,随机(随机数字法)分为正常对照组(A组,n=10)、创伤弧菌脓毒症组(B组,n=50,采用大鼠左下肢皮下注射创伤弧菌悬液制作创伤弧菌脓毒症大鼠模型)及血必净干预组(C组,n=50,感染后0.5 h腹腔注射血必净4 mL/kg).B、C组大鼠于染菌后1,6,12,24,48 h麻醉后活杀,留取右肺标本.观察大鼠行为学变化,采用考马斯亮蓝法测肺通透性,采用逆转录-聚合酶链式反应(RT-PCR)法测肺MMP-2/9,TIMP-1/2 mRNA的表达,免疫组化法和双抗体夹心酶联免疫吸附法(ELISA)测肺MMP-2/9和TIMP-1/2的表达.数据采用单因素方差分析,并用LSD-t法进行组间两两比较,以P＜0.05为差异有统计学意义.结果 B组和C组肺通透性显著高于A组,C组显著低于B组.B组和C组MMP-2/9,TIMP-1/2mRNA显著升高,B组分别于6 h(0.344±0.108),6 h(1.230±0.377),12 h(0.523±0.098),12 h(0.280±0.070)达高峰(P＜0.05),C组分别于12 h(0.256±0.074),6 h(0.968±0.225),12 h(0.746±0.316),12 h(0.356±0.035)达高峰(P＜0.05),C组MMP-2/9mRNA升高趋势显著低于B组(P＜0.05),TIMP-1/2mRNA显著高于B组(P＜0.05).B组和C组MMP-2/9,TIMP-1/2蛋白也升高,B组分别于12 h(0.692±0.191),12 h(0.061±0.017),24 h(1384.42±91),24 h(41.04±3.60)达高峰(P＜0.05);C组分别于24 h(0.217±0.065),12 h(0.045±0.013),24 h(1617.22±103),24 h(47.66±3.58)达高峰(P＜0.05);C组MMP-2/9蛋白升高趋势低于B组(P＜0.05),TIMP-1/2蛋白早期与B组差别不大,后期显著高于B组(P＜0.05).结论 MMP/TIMP比例失衡是创伤弧菌脓毒症大鼠肺损伤机制之一,血必净可促进MMP/TIMP比例恢复平衡,对创伤弧菌脓毒症大鼠肺损伤具有保护作用.

Abstract：

Objective To detect the expression of MMP-2/9 and TIMP-1/2 in the lung of Vibrio vulnificus sepsis rats and observe the intervention of Xuebijing injection. Method One hundred and ten SD rats of clean grade were randomly(random number) divided into normal control group (group A, n = 10),Vibrio vulnificus sepsis group (group B, n = 50. Sepsis was reproduced in rats with subcutaneous injection in left lower limb with Vibrio vulnificus) and Xuebijin intervention group ( group C, n = 50. Rats were intraperitoneal(ip) with the dose of Xuebijing 4mL/kg at the time of 30 min later after infection). The rats in group B and C were sacrificed at 1 h, 6 h, 12 h, 24 h, 48 h after infection, the expression of MMP-2/9 and TIMP-1/2 were examined by PCR, Immunohistochemistry or ELISA methods, the lung permeability were measured by Coomassie Brilliant Blue method. Experimental data used single factor analysis of variance, and between groups by LSD method for pairwise comparison,P ＜0.05 statistically significant difference. Results The lung permeability increased both in group B and C compared with group A,and in group B were relatively higher. The lung MMP-2/9, TIMP-1/2mRNA expression in groups B and C compared with in group A was markedly higher, and reached the peak at 6 h(0. 344 ± 0. 108 ),6 h ( 1. 230 ± 0.377 ), 12 h (0.523 ±0.098),12 h(0.280±0.070) (P＜0.05) in group B while at 12 h(0.256 ±0.074),6 h(0.968±0.225) ,12 h(0.746 ±0. 316) ,12 h(0.356 ±0.035) (P ＜0. 05) in group C; the MMP-2/9mRNA expression in group C decreased(P＜0. 05) compared with the group B while the TIMP-1/2mRNA expression increased(P＜0. 05). The lung MMP-2/9, TIMP-1/2 protein expression in groups B and C compared with the group A(0.345±0.109) also increased, and the peak was at 12 h (0. 692 ± 0. 191 ), 12 h (0. 061 ±0.017) ,24 h(1384.42 ±91) ,24 h(41.04 ±3.60)in group B while at 24 h(0. 217 ±0.065) ,12 h(0. 045± 0. 013 ) ,24 h ( 1617.22 ± 103 ) ,24 h (47.66 ± 3.58 )in group C, the MMP-2/9 protein expression in group C was lower than in group B(P＜0.05), the TIMP-1/2 protein expression in group C was similar to in group B early while marked increased(P＜0.05)later. Conclusions MMP/TIMP imbalance was one of the mechanisms of the lung injury in the rats with Vibrio vulnificus sepsis, Xuebijing could restore the balance of MMP/TIMP ratio.     

FOXP1 and SPINK1 reflect the risk of cirrhosis progression to HCC with HBV infection

BackgroundHepatocellular carcinoma (HCC) deriving from cirrhosis with HBV infection harbors higher morbidity and poor prognosis. The diagnosis of HCC at its early stage is essential for improving the effect of treatment and survival rate of patients.MethodAffymetrix GeneChip was practiced to establish gene expression profile and significance analysis of microarray (SAM) as well as prediction analysis of microarray (PAM) was utilized to screen candidate marker genes in tissue of carcinoma and para-cancerous with cirrhosis from 15 hepatitis B virus (HBV) related HCC patients.ResultTotal 497 differential genes were selected by microarray (fold change >2; P value < 0.01). Then 162 significant genes were determined by SAM (fold change −1.46 to 1.28). A number of 8-genes showing “poor risk signature” was validated with threshold of 6.2, which was associated with cirrhosis progressing to HCC. Only 3 down-regulated and 2 up-regulated predictor genes had statistical difference in HCC and cirrhosis groups by RT-PCR (P value < 0.01). Forkhead box protein 1 (FOXP1) and serine protease inhibitor Kazal-type 1 (SPINK1) proteins were found significantly increased in carcinoma tissues than para-cancerous cirrhotic tissues by IH and WB.ConclusionOver-expression of FOXP1 and SPINK1 may participate in the carcinogenesis of HBV related cirrhosis. They could use as potential biomarkers for diagnosing early HCC.     

B细胞激活因子与糖尿病的相关性研究进展

B细胞激活因子(BAFF)是由人类TNFSF13B基因编码的蛋白质,属肿瘤坏死因子超家族成员。近年来多项研究表明,BAFF与脂质代谢、1型糖尿病、2型糖尿病具有相关性。本文主要通过对近几年文献的整理,归纳BAFF与脂质代谢和糖尿病的关系,为糖尿病的诊断和治疗指提供新的思路。     

Hypertension in transgenic (mREN2)27 rats is not associated with the presence of B1 receptors

B1 receptors are inducible receptors expressed only in stressful conditions. The aim of this study was to determine if, in (mREN2)27 transgenic rats, hypertension is associated with the presence of B1 receptors in the cardiovascular system and if a heat stress inducible effect is preserved during hypertension. Age-matched (16 weeks old) heterozygous hypertensive transgenic (mREN2)27 rats (HT rats) and the normotensive control animals (homozygous Sprague-Dawley rats, NT rats) were used. The study was conducted in two parts: in the first part the responsiveness of B1 receptors was studied in rats submitted to heat stress (42 degrees C rectal temperature, 20 min) or sham anaesthesia 24 h before, by recording changes in isometric tension in aortic rings in response to [des-Arg9]-bradykinin, a B1 receptor agonist. In the second part, we studied whether B1 receptor mRNA was present in aorta, heart and kidneys, using a semi-quantitative RT-PCR technique. [des-Arg9]-Bradykinin induced a concentration-dependent relaxation of aortic rings only from animals submitted to prior heat stress. This response was significantly higher in aortic rings from heat stressed HT rats than from heat stressed NT ones. B1 receptor mRNA was undetectable in organs from rats not submitted to heat stress but they were present 5 h after heat stress in aorta, heart and kidneys from both NT and HT rats. In conclusion, arterial hypertension observed in (mREN2)27 rats is not associated with the presence of B1 receptors. However, after heat stress, we observed an increase in responsiveness from HT rat aortas compared to NT ones.