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1.
丹皮酚对豚鼠心肌细胞动作电位及钙通道电流的影响   总被引:18,自引:0,他引:18  
目的 :研究丹皮酚对分离的单个豚鼠心肌细胞动作电位及钙通道电流 (ICa)的影响。方法 :单个细胞膜片钳技术。结果 :①丹皮酚 40 0 μg/ml可使动作电位时程 (APD)明显缩短。APD50 和APD90 分别由给药前的 (35 2±2 7)ms和 (416± 33)ms缩短至 (16 8± 2 0 )ms和 (2 6 5± 2 3)ms(P <0 .0 5 ,n =5 ) ,分别缩短了 5 2 .2 %和 35 .6 % ,而静息电位和动作电位幅值无明显改变 ;② 5 0~ 40 0 μg/ml丹皮酚浓度依赖性阻滞ICa,使其最大峰值由 (916 .7± 197.3)pA分别降至 (5 83 .3± 10 8.8)pA和 (2 5 0 .0± 12 0 .0 )pA(P <0 .0 1) ,抑制率分别为 36 .4%和 72 .7% ,并使ICa的I V曲线上移 ,但不使I V曲线发生偏移。结论 :丹皮酚对ICa的阻滞作用为其抗心律失常作用的主要机制之一  相似文献   

2.
三七总皂甙对大鼠心肌细胞L-型钙电流的抑制作用   总被引:4,自引:0,他引:4  
目的 :探讨三七总皂甙对大鼠心肌细胞L -型钙电流 (ICa-L)的抑制作用 .方法 :采用全细胞膜片钳方法分别观测不同浓度三七总皂甙对大鼠心肌细胞L -型钙电流的抑制作用 .结果 :PNS 10 0mg/L和30 0mg/L对ICa -L的抑制率分别为 (2 6 73± 4 5 ) %和 (4 9± 19 6 ) % (P <0 0 1) .结论 :三七总皂甙能阻滞大鼠心肌细胞ICa -L,并呈剂量依赖性  相似文献   

3.
目的 研究冬虫夏草 (Codycepssinensis,CS)水提液对豚鼠单个心室肌细胞胞浆内钙离子浓度 ([Ca2 ]i)及L 型钙电流 (ICa L)的影响。方法 酶解法分离豚鼠单个心室肌细胞 ,应用激光扫描共聚焦显微镜联合全细胞膜片钳技术测定豚鼠心室肌细胞 [Ca2 ]i以及ICa L的变化。结果 应用 0 1mg/mL (生药浓度 )冬虫夏草水提液 ,在静息状态下对 [Ca2 ]i 无影响 ;对 6 0mmol/LKCl诱导的胞浆 [Ca2 ]i升高有促进作用 ,峰值荧光强度在 12 0s时由12 0 4 3± 2 38 4增加至 185 5 2± 32 1 0 (n =6 ,P <0 0 5 )。膜片钳研究结果表明 ,冬虫夏草水提液可明显促进ICa L,使ICa L从 (- 15 1± 2 3)pA/ pF增加到 (- 19 7± 3 2 ) pA/pF (刺激电压为 10mV ,n =8,P <0 0 1)。 结论 冬虫夏草水提液促进心肌细胞钙内流 ,是该药治疗缓慢型心律失常的机制之一。  相似文献   

4.
目的 研究自发性高血压大鼠 (SHR)左心室肌细胞的电生理特性。方法 以正常血压Wistar大鼠左心室肌细胞作为对照 ,采用玻璃微电极技术记录动作电位 ,应用膜片钳全细胞技术记录膜离子流 ,观察SHR左心室肌细胞动作电位及膜离子流的改变。结果 ①SHR和Wisar大鼠的心脏 /体重比分别为 5 .6 6± 0 .46mg/g(n =2 0 )和 3.7± 0 .2 9mg/g(n =2 8) (P <0 .0 0 1) ,平均细胞膜电容分别为 2 80 .6 8± 6 7.98pF(n =91)和 189.94± 5 6 .5 9pF(n =137) (P <0 .0 5 )。②SHR左心室肌细胞动作电位时程较Wistar大鼠明显延长 [APD50 :2 1.33± 1.5 6ms(n =6 ) ,vs 14.91± 2 .95ms(n =11) ,P <0 .0 0 1;APD90 :16 4.6 7± 4ms ,vs 93.2 7± 10 .5 9ms ,P <0 .0 0 1]。③内向电流 :SHR左心室肌细胞的ICa -L密度与Wistar大鼠间无差异 [6 .93± 1.71pA/pF(n =2 0 ) ,vs 6 .19± 2 .85pA/pF(n =37) ],但前者的慢失活时间常数显著延长 (5 6 .0 1± 13.36ms,vs 43.6 3± 17.89ms,P <0 .0 0 1)。SHR左心室肌细胞的INa密度与Wistar大鼠间无差异 [2 4.6 1± 6 .72 pA/pF(n =16 ) ,vs 2 4.95± 6 .99pA/pF(n =18) ]。④外向电流 :SHR左心室肌细胞IK1内向电流密度显著小于Wistar大鼠 [- 12 0mV时 ,11.3± 2 .2 6 pA/pF(n =17) ,v  相似文献   

5.
目的测定犬右心室三层心肌细胞上参与离子流平衡的内向电流L型钙电流(ICa.L)的特性,并研究其对异丙肾上腺素的反应。方法经酶解分离获得犬右心室外膜下细胞、M细胞和内膜下细胞,应用全细胞膜片钳技术,记录并比较不同部位心肌细胞的ICa.L,分析使用异丙肾上腺素前后电流-电压曲线的差异。结果ICa.L的峰值电流密度(pA/pF)在右心室外膜下细胞、M细胞和内膜下细胞分别为-4.868±1.362(n=20),-3.594±0.544(n=20)和-2.874±0.547(n=20),差异有统计学意义(F=33.493,P<0.05)。使用0.5μmol/L异丙肾上腺素后,右心室外膜下心肌细胞ICa.L的峰值电流密度由-4.832±1.127(n=11)增至-22.348±4.057(P<0.01),M细胞由-3.726±1.051(n=11)增至-17.992±4.159(P<0.01),心内膜下心肌细胞用药前后变化(-2.714±0.879,-2.987±1.012)差异无统计学意义(P>0.05)。结论ICa.L在犬右心室肌的不同细胞(外膜下心肌细胞、M细胞、内膜下心肌细胞)存在不均一性,β-肾上腺能激动剂可以减小右心室外膜下心肌细胞和M细胞动作电位复极1期末离子流的外向转移。  相似文献   

6.
目的测定犬左、右心室3层心肌细胞上参与离子流平衡的内向电流L型钙电流(ICa.L)的特性。方法经酶解分离获得犬左、右心室外膜下细胞、M细胞和内膜下细胞,应用全细胞膜片钳技术,记录并比较不同部位心肌细胞的ICa.L,分析电流-电压曲线。结果ICa.L的峰值电流密度(pA/pF)在右心室外膜下细胞、M细胞和内膜下细胞分别为:-4.896±1.907(n=31),-3.406±0.904(n=37)和-2.788±0.756(n=33),心外膜下心肌细胞与M细胞比较,差异有统计学意义(P<0.05);在左心室分别为:-3.824±1.201(n=18),-4.854±1.485(n=20)和-2.988±1.082(n=17),3者之间两两比较,差异有统计学意义(P<0.05)。ICa.L的峰值电流密度在右心室心外膜下心肌细胞大于左心室(P<0.05),而右心室M细胞小于左心室(P<0.01),心内膜下心肌细胞左、右心室之间差异无统计学意义(P>0.05)。结论ICa.L在犬左、右心室肌的不同细胞(外膜下心肌细胞、M细胞、内膜下心肌细胞)存在不均一性,导致右心室跨室壁的电不均一性较左心室明显。  相似文献   

7.
去甲肾上腺素对豚鼠缺血及再灌注性室颤的作用   总被引:2,自引:0,他引:2  
目的 :探讨去甲肾上腺素 (NE)在缺血性室颤及缺血 /再灌注性室颤发生中的作用及机制。方法 :运用高效液相色谱 电化学法测定离体豚鼠缺血性室颤心脏 (n =2 4 )及缺血 /再灌注性室颤心脏 (n =2 6 )流出液中NE的含量 ,并与未发生室颤心脏 (n =2 9)相比较 ,用全细胞膜片钳记录技术检测NE对缺氧豚鼠心肌细胞 (n =8)钙通道电流 (ICa)的影响。结果 :发生缺血性室颤心脏及缺血 /再灌注性室颤心脏NE释放量明显高于未发生室颤心脏 (P <0 0 1) ;NE可明显增加缺血及缺血 /再灌注心肌细胞ICa(P <0 0 1,P <0 0 5 )。结论 :NE增加心肌细胞ICa为其致缺血及缺血 /再灌注性室颤的机制之一。  相似文献   

8.
目的 以往的研究表明血管紧张素Ⅱ (AngⅡ )对心室肌细胞L型钙流 (ICa,L)的影响及作用机制尚有争议。本文应用AngⅡ 1型受体 (AT1)阻滞剂Losartan和蛋白激酶C(PKC)抑制剂H 7来研究AngⅡ对单个豚鼠心室肌细胞ICa ,L的作用及机制。方法 应用膜片钳技术研究AngⅡ对单个豚鼠心室肌细胞ICa ,L影响的细胞机制。结果 结果表明 ,在膜片钳全细胞记录模式 ,AngⅡ刺激ICa ,L,呈浓度依赖性 ,最大作用浓度为 10 0nmol/L (n =9)。30nmol/L的AngⅡ使ICa ,L峰电流由 11 3± 0 6pA/pF增大为 15 3± 0 6pA/pF( 10mV ,n =9,P <0 0 5)。 10 0nmol/L的Losartan本身对ICa ,L无影响 ,但可抑制AngⅡ对ICa,L的作用。AngⅡ对ICa,L的作用也能被 2 0nmol/L的H 7所抑制 ,而H 7本身对ICa,L无影响。结论 以上结果提示AngⅡ经AngⅡ 1型受体刺激ICa,L,这一作用经由PKC介导而实现。  相似文献   

9.
目的 观察雌激素对大鼠心肌细胞钙转运的调控作用 .方法 应用膜片钳全细胞记录方法观察 L型钙通道电流 (ICa.L) ,共聚焦显微镜系统分析细胞内钙浓度 ([Ca2 +]i)的变化 .结果 应用 10 μmol· L- 1和 30 μmol· L- 1的 17β- Estradiol,分别使 ICa.L抑制到正常的 (4 8.1± 4.5 ) %和 (2 9.3± 5 .2 ) % (n=5 ,P<0 .0 1) . 10μmol· L- 1 的 17β- Estradiol可升高静息的培养心肌细胞[Ca2 +]i,荧光强度 (FI)值由 5 4.2± 13.6增加到 86 .5± 15 .3(n=6 ,P<0 .0 1) ;而对具有自发收缩的心肌细胞钙瞬变幅度有明显的抑制作用 ,由给…  相似文献   

10.
目的 研究模拟失重大鼠心肌细胞钙电流 (ICa)对β-肾上腺素受体激动剂的反应性变化 .方法 用尾部悬吊大鼠模型模拟失重 (4 wk) ,胶原酶分离心肌细胞 ,用膜片钳全细胞方式记录单个心肌细胞的膜电容和 ICa等 .给予β-肾上腺素受体激动剂 (异丙肾上腺素 ) ,记录观察 ICa的反应性 .结果 对照组与悬吊组的 ICa密度无明显差别 (P>0 .0 5 ) ,ICa电流密度 -电压曲线基本一致 ;加入异丙肾上腺素后 ,两组 ICa密度均明显增大 ,但是两组的增加幅度不同 ,悬吊组的增加幅度 (84.3± 8.2 ) %明显小于对照组 (10 9.3± 7.9) % (P<0 .0 5 ) .结论 模拟失重 4wk大鼠心肌细胞的 ICa密度无明显改变 ;模拟失重后心肌细胞 ICa对 β-肾上腺素受体激动剂的反应性降低  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

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