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1.
Jan CR  Tseng CJ  Chen WC 《Life sciences》2000,66(11):1053-1062
The effect of fendiline, a documented inhibitor of L-type Ca2+ channels and calmodulin, on Ca2+ signaling in Madin Darby canine kidney (MDCK) cells was investigated using fura-2 as a Ca2+ probe. Fendiline at 5-100 microM significantly increased [Ca2+]i concentration-dependently. The [Ca2+]i rise consisted of an initial rise and a slow decay. External Ca2+ removal partly inhibited the Ca2+ signals induced by 25-100 microM fendiline by reducing both the initial rise and the decay phase. This suggests that fendiline triggered external Ca2+ influx and internal Ca2+ release. In Ca(2+)-free medium, pretreatment with 50 microM fendiline nearly abolished the [Ca2+]i rise induced by 1 microM thapsigargin, an endoplasmic reticulum Ca2+ pump inhibitor, and vice versa, pretreatment with thapsigargin prevented fendiline from releasing internal Ca2+. This indicates that the internal Ca2+ source for fendiline overlaps with that for thapsigargin. At a concentration of 50 microM, fendiline caused Mn2+ quench of fura-2 fluorescence at the 360 nm excitation wavelenghth, which was inhibited by 0.1 mM La3+ by 50%, implying that fendiline-induced Ca2+ influx has two components separable by La3+. Consistently, 0.1 mM La3+ pretreatment suppressed fendiline-induced [Ca2+]i rise, and adding La3+ during the rising phase immediately inhibited the signal. Addition of 3 mM Ca2+ increased [Ca2+]i after preincubation with 50-100 microM fendiline in Ca(2+)-free medium. However, 50-100 microM fendiline inhibited 1 microM thapsigargin-induced capacitative Ca2+ entry. Pretreatment with 40 microM aristolochic acid to inhibit phospholipase A2 inhibited 50 microM fendiline-induced internal Ca2+ release by 48%, but inhibition of phospholipase C with 2 microM U73122 or inhibition of phospholipase D with 0.1 mM propranolol had no effect. Collectively, we have found that fendiline increased [Ca2+]i in MDCK cells by releasing internal Ca2+ in a manner independent of inositol-1,4,5-trisphosphate (IP3), followed by external Ca2+ influx.  相似文献   

2.
The effect of fendiline, an anti-anginal drug, on cytosolic free Ca2+ levels ([Ca2+]i) in A10 smooth muscle cells was explored by using fura-2 as a Ca2+ indicator. Fendiline at concentrations between 10-50 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 of 20 microM. External Ca2+ removal reduced the Ca2+ signal by 75%. Addition of 3 mM Ca2+ increased [Ca2+]i in cells pretreated with fendiline in Ca2+-free medium. The 50 microM fendiline-induced [Ca2+]i increase in Ca2+-containing medium was inhibited by 10 microM of La3+, nifedipine, or verapamil. In Ca2+-free medium, pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) to deplete the endoplasmic reticulum Ca2+ store partly inhibited 50 microM fendiline-induced Ca2+ release; whereas pretreatment with 50 microM fendiline abolished 1 microM thapsigargin-induced Ca2+ release. Inhibition of phospholipase C activity with 2 microM U73122 did not alter 50 microM fendiline-induced Ca2+ release. Incubation with 50 microM fendiline for 10-30 min decreased cell viability by 10-20%. Together, the findings indicate that in smooth muscle cells fendiline induced [Ca2+]i increases. Fendiline acted by activating Ca2+ influx via L-type Ca2+ channels, and by releasing internal Ca2+ in a phospholipase C-independent manner. Prolonged exposure of cells to fendiline induced cell death.  相似文献   

3.
Lin MC  Jan CR 《Life sciences》2002,71(9):1071-1079
The effect of the anti-anginal drug fendiline on intracellular free Ca(2+) levels ([Ca(2+)](i)) in a rabbit corneal epithelial cell line (SIRC) was explored using fura-2 as a fluorescent Ca(2+) indicator. At a concentration above 1 microM, fendiline increased [Ca(2+)](i) in a concentration-dependent manner with an EC(50) value of 7 microM. The [Ca(2+)](i) response consisted of an immediate rise and an elevated phase. Extracellular Ca(2+) removal decreased half of the [Ca(2+)](i )signal. Fendiline induced quench of fura-2 fluorescence by Mn(2+) (50 microM), suggesting the presence of Ca(2+) influx across the plasma membrane. This Ca(2+) influx was abolished by La(3+) (50 microM), but was insensitive to dihydropyridines, verapamil and diltiazem. Fendiline (10 microM)-induced store Ca(2+) release was largely reduced by pretreatment with thapsigargin (1 microM) (an endoplasmic reticulum Ca(2+) pump inhibitor) to deplete the endoplasmic reticulum Ca(2+). Conversely, pretreatment with 10 microM fendiline abolished thapsigargin-induced Ca(2+) release. Fendiline (10 microM)-induced Ca(2+) release was not altered by inhibiting phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122). Cumulatively, this study shows that fendiline induced concentration-dependent [Ca(2+)](i )increases in corneal epithelial cells by releasing the endoplasmic reticulum Ca(2+) in a phospholipase C-independent manner, and by causing Ca(2+) influx.  相似文献   

4.
Ca(2+)-antagonists change the contractility of isolated detrusor smooth muscle of rabbit influencing the translocation of intra- and extra-cellular Ca2+. This observation might be of clinical importance in the treatment of disorders of urinary bladder function. During field stimulation of different segments of isolated rabbit bladder it was found that the specific Ca(2+)-antagonist nifedipine and verapamil and the non-selective Ca(2+)-antagonist fendiline, prenylamine and cinnarizine blocked the contractions induced by field stimulus to different extent, which decreased from the bladder towards the bladder base (fundus). The highest rate of blocking effect was produced by nifedipine followed by verapamil, prenylamine and fendiline, respectively. Cinnarizine exerted the lowest effect. The change in amplitude and frequency of spontaneous peristalsis was similar in its tendency to the blockade of the field stimulus induced contraction.  相似文献   

5.
Ras proteins regulate signaling pathways important for cell growth, differentiation, and survival. Oncogenic mutant Ras proteins are commonly expressed in human tumors, with mutations of the K-Ras isoform being most prevalent. To be active, K-Ras must undergo posttranslational processing and associate with the plasma membrane. We therefore devised a high-content screening assay to search for inhibitors of K-Ras plasma membrane association. Using this assay, we identified fendiline, an L-type calcium channel blocker, as a specific inhibitor of K-Ras plasma membrane targeting with no detectable effect on the localization of H- and N-Ras. Other classes of L-type calcium channel blockers did not mislocalize K-Ras, suggesting a mechanism that is unrelated to calcium channel blockade. Fendiline did not inhibit K-Ras posttranslational processing but significantly reduced nanoclustering of K-Ras and redistributed K-Ras from the plasma membrane to the endoplasmic reticulum (ER), Golgi apparatus, endosomes, and cytosol. Fendiline significantly inhibited signaling downstream of constitutively active K-Ras and endogenous K-Ras signaling in cells transformed by oncogenic H-Ras. Consistent with these effects, fendiline blocked the proliferation of pancreatic, colon, lung, and endometrial cancer cell lines expressing oncogenic mutant K-Ras. Taken together, these results suggest that inhibitors of K-Ras plasma membrane localization may have utility as novel K-Ras-specific anticancer therapeutics.  相似文献   

6.
Phosphatidylserine (PS) is a critical lipid factor in the assembly and spread of numerous lipid‐enveloped viruses. Here, we describe the ability of the Ebola virus (EBOV) matrix protein eVP40 to induce clustering of PS and promote viral budding in vitro, as well as the ability of an FDA‐approved drug, fendiline, to reduce PS clustering and subsequent virus budding and entry. To gain mechanistic insight into fendiline inhibition of EBOV replication, multiple in vitro assays were run including imaging, viral budding and viral entry assays. Fendiline lowers PS content in mammalian cells and PS in the plasma membrane, where the ability of VP40 to form new virus particles is greatly lower. Further, particles that form from fendiline‐treated cells have altered particle morphology and cannot significantly infect/enter cells. These complementary studies reveal the mechanism by which EBOV matrix protein clusters PS to enhance viral assembly, budding, and spread from the host cell while also laying the groundwork for fundamental drug targeting strategies.  相似文献   

7.
Capillary isotachophoresis was applied for the determination of fendiline and gallopamil – calcium antagonists – in serum. The cationic electrolyte system containing Na+ with acetic acid as a counter constituent was used as a leading electrolyte with the pH 4.7 and the terminating electrolyte was β-alanine. Most of the proteins were precipitated with methanol, ethanol and dimethylketone. The lowest limits of quantitation were obtained for the pretreatment of serum with methanol. The recoveries of both compounds varied from 91.3 to 97.5%. The relative standard deviations varied from 0.6 to 7.7%.  相似文献   

8.
目的:探讨尿中性粒细胞明胶酶相关载脂蛋白(neutrophil gelatinase-associated lipocalin,NGAL)、尿肾损伤分子-1(kidneyinjury molecule-1,Kim-1)、尿N-乙酰-β-D-氨基葡萄糖苷酶(N-acecyl-β-D-glucosaminidase,NAG)、尿微量白蛋白(mALB)在重症感染中合并急性肾损伤的敏感性及临床价值。方法:回顾分析60例在新疆自治区人民医院ICU住院的重症感染合并急性肾损伤(AKI)患者的尿NGAL、Kim-1、NAG及mALB的变化情况。健康体检者20例为对照组。尿NGAL、Kim-1、mALB测定采用酶联免疫法(ELISA)检测,尿NAG测定采用对硝基苯酚(PNP)比色法检测,并以ROC曲线分析其敏感性。结果:AKI组患者尿液中的NGAL、Kim-1、NAG、mALB的测定浓度明显高于对照组,差异具有统计学意义(P<0.001),通过ROC曲线、诊断试验结果显示:尿NGAL、Kim-1曲线下面积分别为0.986、0.956,95%可信区间分别是0.968~1.004、0.910~1.001,较尿NAG、mALB更具有敏感性(P<0.001)。结论:尿NGAL、尿Kim-1的浓度检测对重症感染合并急性肾损伤的诊断更具有敏感性,与NAG、mALB联合检测有助于急性肾损伤的早期监测,对预防急性肾损伤的发生、发展具有重要的临床价值。  相似文献   

9.
目的:探讨尿微量蛋白联合血清纤维蛋白原在冠心病的诊断价值。方法:选取同期在我院治疗的24例稳定型心绞痛的患者,36例诊断为不稳定型心绞痛的患者和30例诊断为急性心肌梗死的患者,并选择同期30例来我院体检健康志愿者为对照组。分析以上4组患者发病时尿微量蛋白及血清纤维蛋白原的变化情况。结果:与对照组比,3个冠心病组的尿微量蛋白及血清纤维蛋白原的含量显著升高(P<0.05),与稳定型心绞痛组比,不稳定型心绞痛组的尿微量蛋白及血清纤维蛋白原的含量显著升高(P<0.05);与不稳定型心绞痛组比,急性心梗的尿微量蛋白及血清纤维蛋白原的含量显著升高(P<0.05)。3组病患的尿微量蛋白及血清纤维蛋白原之间呈正相关关系(r=0.852,P<0.05)。结论:心肌梗死和心绞痛患者尿微量蛋白及血清纤维蛋白原含量较健康成人含量高,提示尿微量蛋白及血清纤维蛋白原的含量有助于对心肌梗死和心绞痛的诊断,对急性心肌梗死的诊断价值较高。  相似文献   

10.
The objective of the study reported here was to investigate three factors that may affect the amounts of water consumed and urine excreted by a rat in the metabolism cage: water dilution, housing, and food. Young F344/N rats (eight per group) were used for all experiments. Food was withheld from rats before each 16-h urine collection, then rats were transferred into a metabolism cage. For trial A (water dilution), urine was collected from rats supplied with dyed water (0.05%, vol/vol). This was repeated three times over a 2-week period. Dye in water or urine was quantified, using a spectrophotometer. For trial B (housing), rats were individually housed in wire cages for 3 weeks before the first urine collection. Then they were group housed in the solid-bottom cage (four per cage). After 2 weeks of acclimation, urine collection was repeated. For trial C (food), one group of rats was provided with food, the other was not, during urine collection. About 8% of urine samples of small volume (< or = 3 ml) from trial A were contaminated with drinking water up to 13% of volume. The average urine volume associated with individual housing was approximately twice as large as that associated with group housing. When food was provided during urine collection, rats consumed similar amounts of water but excreted significantly smaller amounts of urine than did rats without food. It was concluded that water dilution of a urine sample from a sipper bottle is relatively small; rats individually housed in wire caging before urine collection can consume and excrete a larger quantity of water, compared with rats group housed in solid-bottom cages; and highly variable urine volumes are, in part, associated with lack of access to food during urine collection.  相似文献   

11.
目的:探讨坦洛新联合托特罗定对老年膀胱过度活动综合症患者P2X3受体表达的影响。方法:收集我院收治的膀胱过度活动综合症患者60例,随机分为对照组和实验组,每组各30例,对照组患者给予盐酸坦洛新缓释胶囊,实验组患者在对照组的基础上给予酒石酸托特罗定。观察并比较所有患者的最大尿流速率、膀胱残余尿量、排尿次数、单次最大尿量水平以及患者的治疗效果。结果:治疗后,两组患者治疗后单次最大尿量、最大尿流速率均升高(P0.05),膀胱残余尿量、排尿次数以及P2X3水平均降低(P0.05);与对照组相比,实验组患者治疗后单次最大尿量、最大尿流速率较高(P0.05),膀胱残余尿量、排尿次数以及P2X3水平较低(P0.05);实验组患者临床总有效率与对照组相比较高(P0.05)。结论:坦洛新联合托特罗定能够显著提高老年膀胱活动度综合征患者临床疗效,可能与其降低患者血清P2X3受体水平有关。  相似文献   

12.
Osteopontin (OPN) is a multifunctional glycosylated phosphoprotein found in body fluids, including urine, and has been implicated in urinary stone formation. We tested the hypothesis that OPN levels in urine of patients with kidney stones differed from normal individuals. To quantify OPN levels in the urine, we developed an ELISA using a combination of a mouse monoclonal and rabbit polyclonal antibodies raised against a recombinant glutathione-S-transferase-human OPN fusion protein. In a group of 34 patients diagnosed with kidney stones compared with a control group of 23 normal individuals, we found that OPN levels in urine of the patient and control groups ranged from 0.01 to 2.7 μg/ml, with no significant difference in their medians (P > 0.8, Mann-Whitney test). OPN in urine was qualitatively assessed by Western blotting using a biotinylated monoclonal antibody to detect various molecular forms. The urine of most individuals contained OPN species within in the 55- to 66-kDa electrophoretic mobility range. However, a significantly higher proportion of individuals in the patient group (13 of 34) was found to have aberrant urine OPN species (≤ 40 kDa) compared to 2 of 23 for the control group (P < 0.03, x2 test). Mixing experiments indicated that urine samples with aberrant OPN contain proteases inhibitable with phenylmethylsulfonyl fluoride. Such proteases could break down normal urine OPN in vitro. Therefore, urine from a high frequency of kidney stone patients contains serine proteases that contribute to proteolytic cleavage of OPN. © 1996 Wiley-Liss, Inc.  相似文献   

13.
目的:探讨甲亢患者β2-微球蛋白含量与血脂水平的相关性。方法:以甲状腺功能亢进症患者40例作为观察组,另选择同期在我院进行体检的健康人群40例为对照组,分别于治疗前和治疗后检测患者血清和尿β2-微球蛋白、血外周血载脂蛋白、血脂,并进行血清和尿β2-微球蛋白与血脂的相关性分析。结果:治疗前甲亢组血清和尿β2-微球蛋白均高于对照组(P〈0.01);TC、TG、HDL-C、LDL-C和APOB均低于对照组(P〈0.01);治疗后,血清和尿β2-微球蛋白与治疗前相比均有所下降(P〈0.01),TC、TG、HDL—C、LDL-C和APOB与脂类前相比均有所升高(P〈0.01);血清和尿β2-微球蛋白与TC、TG、HDL-C、LDL-C和APOB均呈负相关。结论:甲亢患者血清和尿β2-微球蛋白与血脂关系密切,可作为评价患者脂质代谢状态和病情变化的重要指标。  相似文献   

14.
目的:研究来氟米特联合糖皮质激素治疗进展性IgA肾病的疗效及对尿VCAM-1水平的影响。方法:选择2012年5月至2014年5月在我院接受治疗的进展性IgA肾病患者104例作为研究对象。按照随机数字表法分成实验组及对照组各52例,对照组予以常规治疗方案联合泼尼松药物治疗,实验组基于对照组基础另予来氟米特治疗,疗程均为6个月。采用全自动生化分析仪测定并比较两组患者治疗前后24 h尿蛋白定量、血白蛋白、血肌酐、肾小球滤过率(GFR)及尿血管细胞黏附分子(尿VCAM-1)水平,评价治疗后两组患者的临床疗效和药物不良反应。结果:(1)实验组的总有效率为94.23%,显著高于对照组的80.77%(P0.05);(2)两组治疗后尿蛋白定量、血肌酐水平及尿VCAM-1水平均显著低于治疗前,且实验组低于对照组;而治疗后血白蛋白及GFR水平均分别显著高于治疗前,实验组高于对照组(均P0.05);(3)治疗后实验组的药物总不良反应发生率与对照组相比,差异无统计学意义(P0.05)。结论:利用来氟米特与糖皮质激素联合治疗进展性IgA肾病患者,具有较好的疗效,可降低尿VCAM-1水平,且不会增加不良反应的发生,值得在临床推广应用。  相似文献   

15.
目的:探讨糖尿病合并尿路感染患者尿液降钙素原(PCT)水平及其临床意义。方法:选取2017年8月至2018年12月中山大学附属第五医院内分泌与代谢病科收治的糖尿病患者78例,以其中合并真性细菌尿者39例作为观察组,未合并尿路感染39例作为对照组,比较两组患者的临床资料以及相关实验室检查结果,同时留取尿液标本,观察组分别留取使用抗生素治疗前、后的尿液标本。采用酶联免疫吸附测定(ELISA)法检测尿液PCT浓度。分别比较观察组与对照组以及观察组治疗前后的尿液PCT水平,分析尿液PCT水平对于诊断糖尿病合并尿路感染的临床价值。结果:观察组尿液PCT水平为0.030 (0.025,0.039) ng/m L,明显高于对照组0.017 (0.011,0.021) ng/m L(P0.05);观察组有症状尿路感染与无症状细菌尿(ABU)的尿液PCT水平比较差异无统计学意义(P0.05),但其均显著高于对照组(P0.05);观察组使用抗生素治疗后的尿液PCT水平为0.031 (0.025,0.040) ng/mL,与治疗前相比较差异无统计学意义(P0.05)。尿液PCT对糖尿病合并尿路感染诊断的敏感度为82.05%,特异度为79.49%,阳性预测值为80.00%,阴性预测值81.58%,ROC曲线下面积为0.81 (95%CI为0.71-0.89, P0.0001)。结论:尿液PCT水平对糖尿病合并尿路感染有一定的诊断参考价值,但对于抗生素疗效的评估价值还需进一步深入研究。  相似文献   

16.
目的:评价尿液转流在修复尿道下裂术后复杂性尿瘘术中的作用。方法:将40例尿道下裂术后复杂性尿瘘患者随机分为尿液转流组和非尿液转流组两组进行比较。结果:尿液转流组:25例患者术后尿道皮肤瘘复发两例,手术成功率99.2%。非尿液转流组:15例患者中有6例(40%)发生尿瘘复发。结论:尿道下裂术后复杂性尿瘘修复术中应用尿液转流有较好的效果。  相似文献   

17.
目的:观察胰岛素联合百令胶囊治疗早期糖尿病肾病患者的临床疗效,并探讨其可能机制。方法:收集在我院就诊或住院治疗的62例糖尿名肾病患者,随机分为实验组和对照组,每组31例。对照组患者给予诺和灵30R胰岛素,实验组患者在对照组基础上给予百令胶囊治疗。治疗后,对患者的血肌酐、尿蛋白、CD68以及临床疗效进行检测并比较。结果:与治疗前相比,两组患者治疗后的血肌酐、尿蛋白、CD68均下降(P0.05);与对照组相比,实验组患者的血肌酐、尿蛋白、CD68水平较低(P0.05),临床治疗有效率较高(P0.05)。结论:胰岛素联合百令胶囊能够有效提高早期糖尿病肾病患者的临床疗效,可能与其降低血清CD68水平,减轻炎症反应有关。  相似文献   

18.
To determine the effectiveness of precleansing with chlorhexidine gluconate-cetrimide in reducing the contamination rate of bagged urine specimens, 62 infants admitted to a children''s hospital were randomly assigned to either receive (32 infants) or not receive (30) cleansing before bag application. Perimeatal swabs were taken before bag application and, in the treated group, after cleansing. Of the specimens from the treated group 69% were found to be contaminated, compared with 73% of those from the no-cleansing group. Chlorhexidine was ineffective in eliminating the perimeatal flora in 75% of the infants. The same organisms were present on the perimeatal swab and in the urine specimen in 95% of the infants in the treated group and 96% of those in the no-cleansing group. To estimate the contamination rate of urine specimens routinely cultured in the laboratory, 200 consecutive specimens (142 midstream and 58 bagged) were cultured. The contamination rate of the midstream urine specimens was 15%, compared with 66% for the bagged speciments. The cost of laboratory processing of contaminated bagged urine specimens at the hospital in 1983 may have been as high as $13 365. Chlorhexidine cleansing does not appear to be cost-effective. Further randomized controlled studies are needed to evaluate the effectiveness of other cleansing agents in reducing the contamination rate of bagged urine specimens.  相似文献   

19.
目的:检测子痫前期患者尿液中足细胞裂孔膜蛋白和足细胞标记蛋白的浓度并探讨其临床意义。方法:本实验以62例妊娠期妇女为研究对象,分为三组,其中正常妊娠期妇女25例为正常对照组,慢性高血压的妊娠期妇女17例为高血压组,子痫前期患者20例为子痫前期组。ELISA检测各组妊娠期妇女的尿液中足细胞裂孔膜蛋白和足细胞标记蛋白的表达;Bradford法检测各组妊娠期妇女的尿蛋白。结果:足细胞裂孔膜蛋白和足细胞标记蛋白在正常对照组尿液中含量极少,在高血压组中分泌增加,而子痫前期组患者中明显升高(P〈0.01),且在子痫前期组尿液中足细胞裂孔膜蛋白和标记蛋白的分泌含量均成正相关(r2=0.79,P〈0.05)。子痫前期组患者中足细胞裂孔膜蛋白和足细胞标记蛋白与尿蛋白浓度成正相关(r2=0.58,P〈0.05;r2=0.79,P〈0.05)。结论:足细胞蛋白脱落主要发生于子痫前期患者,且足细胞蛋白脱落量与尿蛋白成正相关,能直接反映妊娠期患者的肾损伤程度,可作为预测罹患妊娠期高血压的指标。  相似文献   

20.
The most fundamental property of biomarkers is change. But changes are hard to maintain in plasma since it is strictly controlled by homeostatic mechanisms of the body. There is no homeostatic mechanism for urine. Besides, urine is partly a filtration of blood, and systematic information can be reflected in urine. We hypothesize that change of blood can be reflected in urine more sensitively. Here we introduce the interference into the blood by two anticoagulants heparin or argatroban. Plasma and urine proteins were profiled by LC-MS/MS and then validated by Western blot in totally six SD female rats before and after the drug treatments. In argatroban treated group, with exactly the same experimental procedure and the same cutoff value for both plasma and urine proteins, 62 proteins changed in urine, only one of which changed in plasma. In heparin treated group, 27 proteins changed in urine but only three other proteins changed in plasma. Both LC-MS/MS and Western blot analyses demonstrated drug-induced increases in transferrin and hemopexin levels in urine but not in plasma. Our data indicates that urine may serve as a source for more sensitive detection of protein biomarkers than plasma.  相似文献   

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