EH伴左心室肥大患者血浆IMD、血清CysC、CST和Salusin-α测定的临床价值

目的:为探讨原发性高血压(essential hypertension,EH)和EH伴左心室肥厚[EH伴LVH(下分组简称为LVH)]患者的发病机制和测定的临床价值。方法:血浆中叶素(intermedin,IMD)采用放射免疫分析;血清半胱氨酸蛋白酶抑制剂C(CystatinC,CysC)、儿茶酚抑素(catestatin,CST)和新型心血管活性肽Salusin-α测定则应用酶联免疫分析。结果:血浆IMD水平EH组和LVH组均显著地低于正常对照组(P<0.05,P<0.01),且LVH组又显著地低于EH组。血清CysC水平的变化则EH组和LVH组均显著地高于正常对照组(P<0.05,P<0.01),且LVH组又显著地高于EH组。CST水平EH组和LVH组均显著地高于正常对照组(P均<0.05),两组病例比较LVH组略低于EH组(P>0.05)。Salusin-α水平的变化EH组和LVH组均显著低于正常对照组(P均<0.05),两组病例比较LVH组略高于EH组(P>0.05)。结论:四项指标的测定变化,为进一步了解和认识EH和LVH的病理机制可有一定的临床意义。     

Intermedin alleviates the inflammatory response and stabilizes the endothelial barrier in LPS-induced ARDS through the PI3K/Akt/eNOS signaling pathway

Inflammatory storms and endothelial barrier dysfunction are the central pathophysiological features of acute respiratory distress syndrome (ARDS). Intermedin (IMD), a member of the calcitonin gene-related peptide (CGRP) family, has been reported to alleviate inflammation and protect endothelial cell (EC) integrity. However, the effects of IMD on ARDS have not been clearly elucidated. In the present study, clinical ARDS data were used to explore the relationship between serum IMD levels and disease severity and prognosis, and we then established a model to predict the possibility of hospital survival. Mouse models of ARDS and LPS-challenged endothelial cells were used to analyze the protective effect and underlying mechanism of IMD. We found that in patients with ARDS, increased serum IMD levels were associated with reduced disease severity and increased rates of hospital survival. IMD alleviated the LPS-induced inflammatory response by decreasing proinflammatory cytokines, NF-κB p65 expression and NF-κB p65 nuclear translocation. In addition, IMD stabilized the endothelial barrier by repairing adherens junctions (AJs), cytoskeleton and capillary leakage. IMD exerted protective effects against ARDS on pulmonary endothelial cells, at least partly, through PI3K/Akt/eNOS signaling, while IMD’s anti-inflammation effect was mediated through an eNOS-independent mechanism. Our study may provide new therapeutic insight for ARDS treatment.     

垂体中叶素抑制内质网应激拮抗阿霉素诱导的H9c2心肌细胞损伤机制研究

目的 利用阿霉素(doxorubicin,DOX)诱导的H9c2心肌细胞损伤模型研究垂体中叶素(intermedin,IMD)拮抗DOX心脏损伤的药理学作用和机制.方法 建立H9c2细胞的DOX心脏损伤模型,设空白对照组、DOX(2 μmol/L)模型组、IMD受体拮抗剂IMD17-47(1 μmol/L)组和IMD8-47(10-8、10-6和10-5mol/L)3个剂量处理组,采用CCK-8法检测心肌细胞活性,丙二醛(MDA)含量测定评价H9c2细胞的氧化应激水平,Western法检测caspase-3活化片段和内质网应激相关蛋白葡萄糖调节蛋白78(GPR78)的表达水平,并采用Real-time PCR法检测内源性IMD及其受体系统的mRNA表达水平.结果 与对照细胞相比较,DOX处理显著降低细胞存活率、增加细胞内MDA含量、caspase-3活性片段和内质网应激水平.与单纯DOX组相比较,IMD17-47抑制DOX诱导的内源性IMD的作用后明显降低细胞的存活率(P<0.05)、增加细胞内MDA含量(P<0.01)、caspase-3活化片段和内质网应激水平(P<0.01);外源性给予IMD干预呈剂量依赖性地促进DOX处理细胞的存活率、降低细胞的MDA含量、凋亡和内质网应激水平(P<0.05).此外,DOX处理明显增加心脏组织内源性IMD及其受体的mRNA表达.结论 DOX诱导心肌细胞内源性IMD及其受体的表达,内源性IMD和外源性给予的IMD均通过DOX刺激增强的IMD受体系统,有效降低DOX诱导的氧化应激和内质网应激水平,实现其促进心肌细胞存活、抑制细胞凋亡的保护作用.     

IMD在冠状动脉造影及介入治疗前后的变化及临床意义

目的观察IMD在冠状动脉造影及介入治疗前后的变化,以探讨IMD在冠心病疾病过程中的变化规律及临床意义。方法随机选取接受冠状动脉造影及介入治疗患者52例,分别于术前、术后24 h静脉取血获得血浆,采用放免法测定血浆IMD浓度,并与健康对照组(n=20)进行比较。结果冠造介入组患者治疗前IMD水平(pg/ml)明显低于健康对照组(146.85±33.10 vs 189.04±56.89,P<0.05),行冠状动脉造影及介入治疗后IMD水平显著升高(163.76±56.25,P<0.01)。治疗前冠状动脉造影不正常者IMD水平明显低于冠状动脉造影正常患者(135.50±29.34 vs 167.37±18.63,P<0.05),且术后均明显增高(P<0.05)。结论 IMD在冠心病患者中含量较低,其水平的降低可能为冠心病潜在危险因素之一。在行冠状动脉造影及介入治疗后,出现IMD水平的增高,可能与治疗过程中的出现心肌缺血再灌注损伤,机体出现代偿有关。     

Pharmacological characterization of rat amylin receptors: implications for the identification of amylin receptor subtypes

BACKGROUND AND PURPOSE

Amylin (Amy) is an important glucoregulatory peptide and AMY receptors are clinical targets for diabetes and obesity. Human (h) AMY receptor subtypes are complexes of the calcitonin (CT) receptor with receptor activity-modifying proteins (RAMPs); their rodent counterparts have not been characterized. To allow identification of the most clinically relevant receptor subtype, the elucidation of rat (r) AMY receptor pharmacology is necessary.

EXPERIMENTAL APPROACH

Receptors were transiently transfected into COS-7 cells and cAMP responses measured in response to different agonists, with or without antagonists. Competition binding experiments were performed to determine rAmy affinity.

KEY RESULTS

rCT was the most potent agonist of rCT_(a) receptors, whereas rAmy was most potent at rAMY_1(a) and rAMY_3(a) receptors. rAmy bound to these receptors with high affinity. Rat α-calcitonin gene-related peptide (CGRP) was equipotent to rAmy at both AMY receptors. Rat adrenomedullin (AM) and rAM2/intermedin activated all three receptors but were most effective at rAMY_3(a). AC187, AC413 and sCT_8-32 were potent antagonists at all three receptors. rαCGRP_8-37 displayed selectivity for rAMY receptors over rCT_(a) receptors. rAMY_8-37 was a weak antagonist but was more effective at rAMY_1(a) than rAMY_3(a).

CONCLUSIONS AND IMPLICATIONS

AMY receptors were generated by co-expression of rCT_(a) with rRAMP1 or 3, forming rAMY_1(a) and rAMY_3(a) receptors, respectively. CGRP was more potent at rAMY than at hAMY receptors. No antagonist tested was able to differentiate the rAMY receptor subtypes. The data emphasize the need for and provide a useful resource for developing new CT or AMY receptor ligands as pharmacological tools or potential clinical candidates.

LINKED ARTICLES

This article is part of a themed section on Secretin Family (Class B) G Protein-Coupled Receptors. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.166.issue-1     

低氧性肺动脉高压大鼠肺组织中介素的分布

目的观察低氧性肺动脉高压大鼠血浆中介素含量及肺组织中介素的分布。方法成年雄性Wistar大鼠被随机分为对照组,低氧1w组、2w组、3w组。对照组置于舱外常氧环境中饲养;其他3组动物置于低压舱内,模拟海拔5000m高度缺氧,每天连续7h。各组大鼠颈总动脉取血,应用放射免疫法检测血浆中介素含量,用免疫组织化学法检测中介素在肺内的分布。结果对照组,低氧1w组、2w组、3w组血浆中介素含量依次为（138．6±5．3）、（154．6±20．2）、（158．8±21．3）、（166．3±12．2）pg／ml,低氧各组大鼠血浆中介素含量增高。低氧3w时升高最明显,明显高于对照组（P〈0．05）。中介素在大鼠肺组织多种细胞中广泛分布。结论中介素在肺动脉高压的病理生理过程中发挥显著作用。     

中介素在人子宫内膜腺癌中的表达及意义

目的检测中介素(Intermedin)在人子宫内膜腺癌组织中的表达,探讨其表达与子宫内膜腺癌临床病理参数以及微血管密度(MVD)的关系。方法应用免疫组化方法检测中介素在子宫内膜单纯性增生、子宫内膜不典型增生和子宫内膜腺癌组织中的表达,通过免疫组化SP法检测组织内微血管密度(MVD),比较中介素表达与肿瘤微血管密度的关系。结果中介素在子宫内膜腺癌中的表达高于子宫内膜单纯性增生及不典型增生中的表达;在子宫内膜腺癌中,中介素的表达与肿瘤的临床FIGO分期呈正相关(P=0.018),与肿瘤的肌层浸润呈正相关(P=0.0004)。中介素的表达与肿瘤的MVD呈正相关(P=0.002)。结论中介素在子宫内膜腺癌的发生发展过程中起到促进作用,并参与肿瘤血管生成。     

尾加压素Ⅱ与中介素在牛磺酸减轻油酸所致大鼠肺损伤中的作用

目的 研究牛磺酸对油酸所致急性肺损伤大鼠的干预作用及其通过影响尾加压素Ⅱ(UⅡ)及中介素(intermedin,IMD)合成与分泌发挥肺保护作用的机制.方法 采用油酸性急性肺损伤大鼠模型.动物分为3组,对照组(C组)、油酸损伤组(A组)、牛磺酸治疗组(T组),分别于0、6、12、24 h4个时间抽动脉血2 mL并取肺泡灌洗液(BALF),测动脉血氧分压[p(O2)],血浆及BALF中UⅡ、IMD浓度,测定肺湿干质量比(W/D)并进行统计学分析;HE染色、免疫组化检查肺组织中UⅡ与IMD表达水平;电镜观察肺组织超微结构.结果 T组p(O2)在6、12、24h时高于A组(P＜0.05);A组肺组织W/D在0h和6h高于T组(P＜0.05);A组血浆UⅡ在24h高于T组(P＜0.05);A、T组BALF UⅡ在0、6h差异显著(P＜0.05),0h时T组高于A组(P＜0.05),6h时A组高于T组(P＜0.05);A组血浆IMD在0h时高于T组(P＜0.05).光镜观察:T组肺组织损伤减轻.免疫组化染色结果显示各组大鼠支气管黏膜上皮细胞、平滑肌细胞,肺内血管内皮细胞、平滑肌细胞细胞膜及细胞质均有UⅡ与IMD阳性表达,A组与T组间表达无明显差异.电镜观察:T组较A组损伤减轻,基底膜完整,未见明显胶原增生.结论 牛磺酸可减轻油酸致大鼠急性肺损伤,其机制可能与抑制UⅡ表达,减轻毛细血管基底膜损伤后肺泡渗出有关.     

败血症休克大鼠心血管组织中介素分泌和表达的变化及对血流动力学的影响

目的观察败血症休克大鼠血浆和心血管组织IMD含量和mRNA表达的变化;探讨内源性IMD1-47对感染性休克大鼠血流动力学的影响。方法盲肠结扎穿孔方法复制大鼠败血症性休克模型;分别用放射免疫法和半定量RT-PCR检测大鼠血浆和心血管组织IMD含量及心血管组织IMDmRNA水平;微渗透泵给予外源性IMD1-47,用四道生理记录仪记录经股动脉和颈总动脉插管测量血流动力学。结果与假手术组比较,休克早、晚期动物呈现严重低血糖和高乳酸血症;休克晚期呈现严重的心力衰竭表现;给予外源性IMD1-47后,明显改善了休克晚期动物低血糖高乳酸血症和心力衰竭。休克早期血浆中IMD的浓度和心血管IMD蛋白分泌及mRNA表达水平均较假手术组增高;休克晚期血浆IMD水平和主动脉IMD蛋白分泌均较假手术组增高;心室肌分泌IMD蛋白较假手术组和休克早期减少;与假手术组和休克早期比较,主动脉IMDmRNA表达水平降低,心室肌IMDmRNA表达水平却增加。结论IMD参与了大鼠感染性休克的病理生理过程,是休克发病的内源性保护物质。     

冠心病患者血浆IMD/ADM-2含量及介入治疗后的变化

目的：研究冠心病患者血浆Intermedin/adrenomedullin 2（IMD/ADM-2）水平的变化以及介入治疗对其的影响,以初步探讨其在该疾病过程中可能扮演的角色。方法：对拟行经皮冠状动脉腔内成形术（PTCA）及支架置入术（CS）的冠心病患者30例,分别于术前、术后24h及72h静脉采血,放免法测定血浆ADM、IMD/ADM-2浓度,并同健康对照组（n=36）进行比较。结果：①冠心病组血浆IMD/ADM-2水平较对照组低36.5%（P〈0.01）,ADM水平则较对照组高64.6%（P〈0.01）。②随着受累冠脉支数的增多,血浆IMD/ADM-2水平呈渐增趋势,而ADM的变化与之相反,但差异无统计学意义（P均〉0.05）。③PTCA＋CS术后24h,血浆ADM、IMD/ADM-2浓度较术前差异无显著性（P均〉0.05）;术后72h,血浆IMD/ADM-2较术前及术后24h分别升高了25.2%和29.2%（P均〈0.05）;而ADM则较术前及术后24h降低了30.6%和22.6%,（P均〈0.05）。④冠心病组血浆ADM与IMD/ADM-2含量间无显著性相关（r=-0.358,P=0.174）。结论：IMD/ADM-2可能与冠心病的发生、发展及转归有关,其作用机理及病理生理学意义可能有别于ADM。