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1.
目的:观察缬沙坦对豚鼠心室肌细胞动作电位的直接作用,以探讨其可能的抗心律失常作用。方法:采用Langendorff主动脉逆行灌流酶解分离法分离单个心室肌细胞。采用全细胞膜片钳记录,电流钳模式记录单个心室肌细胞的动作电位。实验分3组:对照组(n=5),普通细胞外液灌流,不含缬沙坦;缬沙坦5μM组(n=5);缬沙坦100μM组(n=5)。结果:缬沙坦5μM对豚鼠心室肌细胞静息膜电位、动作电位幅度、动作电位时程均无明显影响。缬沙坦100μM可延长心室肌细胞动作屯位时程,尤其是APD50从(334.2±14.4)ms延长至(375.2士12.0)ms(P<0.01)及APD30从(395.4士13.3)ms延长至(451.4±9.5)ms(P<0.01),对细胞静息膜电位、动作电位幅度无显著影响。结论:高浓度缬沙坦延长心室肌细胞动作电位时程APD50及APD90,而不影响动作电位的静息膜电位及动作电位幅度。适度延长动作电位时程,从而延长心室有效不应期,有助于折返引起的快速室性心律失常的防治,类似Ⅲ类抗心律失常药物的作用。提示缬沙坦可能通过此机制起抗心律失常的作用。  相似文献   

2.
目的研究氧化苦参碱对豚鼠心室肌细胞动作电位的影响,探讨氧化苦参碱的抗心律失常作用机制。方法酶解法分解豚鼠单个心室肌细胞,采用全细胞膜片钳技术记录氧化苦参碱对动作电位的影响。结果氧化苦参碱1μmol·L-1对豚鼠单个心室肌细胞静息膜电位和超射值无明显影响;但可使动作电位复极50%时程(APD50)从给药前(534.7±29.62)ms缩短至(490.3±47.39)ms(n=5,P〈0.01),使动作电位复极90%时程(APD90)从给药前(572.1±49.98)ms缩短至(549.8±35.42)ms(n=5,P〈0.01),冲洗后APD50恢复至(498.1±31.78)ms(n=5,P〈0.01),APD90恢复至(554.2±61.28)ms(n=5,P〈0.01)。结论氧化苦参碱可缩短心室肌细胞动作电位时程,提示此机制可能参与氧化苦参碱的抗心律失常作用。  相似文献   

3.
王洪军  赵明 《当代医学》2009,15(32):23-24
目的研究黄芪皂甙(saponins of astrag—alus,SA)对豚鼠心室肌细胞动作电位(AP)的作用。方法实验采用标准玻璃微电极细胞内记录心室肌细胞动作电位(AD)。结果应用9A20mg/L后心室肌细胞动作电位的幅度从给药前的(69.31±6.07)mV降低到(57.37±368)mV(n=6,p〈0.05);动作电位时程(APD40)从给药前的(263.38±16.56)ms延长到(284.55±21.21)ms(n=6,P〈0.05)。应用SA40mg/L后心室肌动作电位的幅度从给药前的(71.37±56.54)mV降低到(47.23±8.67)mV(n=6,p〈0.05);动作电位时程(APD90)的从给药前的(238.31±13.28)ms延长到(314.64±27.36)ms(n=6,p〈0.05)。结论SA可以降低心室肌动作电位幅值延长动作电位时程,并且有一定的剂量依赖性。  相似文献   

4.
目的观察α肾上腺素能受体激动剂间羟胺对大鼠心室肌动作电位及L-型钙电流的影响。方法采用全细胞膜片钳方法,记录离体大鼠心室肌细胞动作电位和L-型钙电流。结果 200μmol/L间羟胺可使心室肌细胞L-型钙电流增大(P〈0.05),动作电位时程(APD)明显延长(P〈0.01),动作电位复极50%和90%时间(APD50and APD90)明显延长(P〈0.01)。100μmol/L酚妥拉明可使增大的的L-型钙电流和APD、APD50、APD明显恢复。结论间羟胺可明显延长大鼠心室肌动作电位时程,而酚妥拉明可不同程度地拮抗此效应。  相似文献   

5.
厄贝沙坦电生理作用的实验研究   总被引:3,自引:0,他引:3  
杨俊  黄从新  江洪  王腾 《医学争鸣》2005,26(1):17-21
目的:研究厄贝沙坦(Irbesartan)对正常豚鼠心室肌细胞L-型钙电流(ICa-L)、内向整流性钾电流(IK1)、快钠流(INa)以及跨膜动作电位的影响.方法:应用膜片钳全细胞记录方法记录各项离子流和跨膜动作电位.结果:①厄贝沙坦呈浓度依赖性阻断ICa-L,10,100和1000 nmol/L的厄贝沙坦分别使ICa-L密度 (pA/pF)从 (-9.8±1.1)减少到(-6.7±0.9),(-4.2±0.8)和(-2.1±0.4)(n=5,P<0.05或P<0.01).②厄贝沙坦可使ICa-L I-V曲线上移,但不改变其激活的电压依赖性和反转电位.③厄贝沙坦呈使用依赖性阻滞ICa-L.④厄贝沙坦对ICa-L激活曲线无明显影响,但可使钙电流稳态失活曲线左移,加速钙通道电压依赖性失活,对照组V1/2和κ值分别为(-30±5)mV,(8.2±0.7),厄贝沙坦组为(-39±7) mV,(11.6±1.3)(n=5,P均<0.05).⑤厄贝沙坦100 nmol/L使ICa-L失活后再激活的恢复时间常数(τ)从对照组(62.5±2.3) ms延长至(126.4±2.6) ms(P<0.01).⑥厄贝沙坦对IK1和INa无明显影响.⑦厄贝沙坦(100 nmol/L)可使单个心室肌细胞动作电位时程(APD30,APD50,APD90)从(106±10),(125±16),(178±23)ms缩短至(82±16),(99±6),(122±18) ms(n=5,P<0.05),对静息电位、动作电位幅度无影响. 结论:厄贝沙坦作用于L-型钙通道的失活态从而阻断ICa-L.  相似文献   

6.
甲醇对豚鼠单个心室肌细胞动作电位的影响   总被引:4,自引:2,他引:2  
目的 研究甲醇对正常豚鼠心室肌细胞跨膜动作电位影响 ,旨在探讨甲醇对心肌细胞的电生理作用。方法 酶解法分离豚鼠单个心室肌细胞 ,应用全细胞膜片钳技术记录甲醇对豚鼠单个心室肌细胞动作电位的影响。结果 应用 0 .2 %甲醇使豚鼠单个心室肌细胞动作电位复极 5 0 %时程 (APD50 )从给药前 (12 92 .6 8± 2 98.0 3)ms缩短到 (75 0 .2 5± 6 8.0 5 )ms (n =6 ,P <0 .0 5 ) ;动作电位复极 90 %时程 (APD90 )从给药前 (132 8.13± 2 89.91)ms缩短到(783.2 5± 6 3.4 4 )ms (n =6 ,P <0 .0 5 ) ;动作电位幅度 (APA)从给药前 (12 6 .35± 3.2 0 )mV减少到 (113.2 0± 6 .0 8)mV(n =6 ,P <0 .0 5 )。结论 甲醇降低动作电位幅度 ,缩短动作电位时程 ,影响心肌正常工作 ,可能与它对心肌细胞钾通道的作用有关。  相似文献   

7.
目的:探讨普罗帕酮对心脏左心室流出道自律细胞与心室肌细胞电生理效应的影响。方法:应用常规的玻璃微电极细胞内记录技术,观察普罗帕酮对豚鼠左心室流出道自律细胞与心室肌细胞动作电位0相幅值(APA),最大除极速率(Vm ax),动作电位时程(APD),50%复极化时间(D50),90%复极化时间(D90)以及左心室流出道自律细胞最大除极速率(Vm ax)与自发电活动频率(HR)。结果:①用0.5μm o l/L的普罗帕酮灌流后与正常对照组相比左心室流出道自律细胞自发电活动频率(HR)显著下降(P<0.01);②用1μm o l/L的普罗帕酮灌流后与正常对照组相比左心室流出道自律细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P<0.05),自发电活动频率(HR)显著下降(P<0.01);用1μm o l/L的普罗帕酮灌流对心室肌细胞的电生理效应影响并不明显。③用5μm o l/L的普罗帕酮灌流后左心室流出道自律细胞电生理活动减弱或消失;用5μm o l/L的普罗帕酮灌流后与正常对照组相比对心室肌细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P<0.05)。④用10μm o l/L的普罗帕酮灌流后与正常对照组相比对心室肌细胞动作电位0幅值(APA)下降(P<0.05),动作电位时程(APD)明显升高(P<0.01),50%复极化时间(D50)及90%复极化时间(D90)升高(P<0.05)。结论:普罗帕酮能抑制左心室流出道自律细胞与心室肌细胞的动作电位0幅值,延长动作电位时程;使左心室流出道自律细胞自发电活动频率下降。  相似文献   

8.
目的:探讨银杏叶提取物(Egb761)对家兔心室肌细胞瞬时外向钾电流(Ito)和动作电位的作用,揭示其抗心肌缺血及缺血引起的心律失常的离子机制。方法:酶解法分离家兔的心室肌细胞。全细胞膜片钳技术记录心肌细胞的Ito和动作电位及其被Egb761作用后的变化。结果:①在电压钳制方式下,60μg/L Egb761作用心室肌细胞5 min后,各个钳制电位下的Ito均明显增大,在钳制电位为+50 mV时,Egb761使Ito的电流密度由对照组的(7.59±0.19)pA/pF增加到(11.18±0.89)pA/pF(P<0.01,n=8),Egb761还使Ito的I-V曲线比对照组Ito的I-V明显抬高,但I-V曲线方向没有发生改变,表明Egb761引起了心肌细胞Ito的明显外流。②在电流钳制下,对照组心室肌细胞动作电位都具有从0期到4期的动作电位形态,60μg/L Egb761使心肌细胞动作电位形态呈三角形尖锥锋形,动作电位时程(APD)明显缩短,其复极化50%时程(APD50)和复极化90%时程(APD90)分别由(83.6±4.3)ms缩短为(51.3±3.2)ms和由(168.7±4.1)ms缩短为(93.8±4.4)ms(分别与对照组相比,P<0.01,n=8),尽管Egb761使动作电位幅度(APA)和静息电位(RP)降低,但与对照组相比,没有显著性差异(P>0.05)。结论:Egb761可使心室肌细胞Ito显著增加和APD明显缩短,从而减轻心肌缺血时细胞内阳离子超载对心肌造成的损伤和心肌缺血引起的心律失常的发生,以及增加心脏泵血功能。  相似文献   

9.
刘念  卜军  阮燕菲 《医学争鸣》2004,25(24):2241-2244
目的: 阐明高胆固醇血症对心脏电生理的影响.方法: 日本大耳白兔分为对照组和高胆固醇饮食组,饲养10 wk后,检测血脂水平,心电图和室颤阈值,并利用全细胞膜片钳技术记录心室肌细胞的ICa,L,组织化学技术检测动脉粥样硬化发生情况.结果: 高胆固醇饮食组兔血脂水平明显高于对照组(P<0.01),粥样硬化广泛分布在动脉血管中.高胆固醇饮食组兔室颤阈值为(11.1±1.3) V,明显低于对照组(14.4±1.6) V,P<0.05.高胆固醇饮食组兔QTc间期(334±14) ms,明显长于对照组(303±12) ms,P<0.05.高胆固醇饮食组心室肌细胞的ICa,L密度为(15.8±1.2)pA/pF,明显高于对照组(11.9±1.0) pA/pF,P<0.01.结论: 高胆固醇血症对心肌细胞的电生理特性有影响,表现在ICa,L的增加,复极时程的延长和室颤阈值的降低.  相似文献   

10.
哇巴因诱发大鼠心律失常作用靶点的研究   总被引:9,自引:2,他引:7  
目的 观察哇巴因对大鼠心室肌细胞动作电位时程、钾通道的作用 ,探讨哇巴因诱发心律失常的作用机制 ,为寻找新的抗心律失常药物提供依据。方法 应用全细胞膜片钳技术记录哇巴因对大鼠心肌细胞动作电位时程 (APD)、内向整流钾电流 (Ik1 )、瞬时外向钾电流 (Ito)的作用。结果 ①哇巴因 5μmol/L使大鼠心室肌细胞动作电位时程从给药前的 86 .3ms± 2 5 .2ms(APD90 ) ,缩短至 58.9ms± 2 0 .8ms(n =5 ,P <0 .0 1 ,给药 1 0min) ;②哇巴因 5μmol/L可增加大鼠心室肌细胞内向整流钾电流 ,使Ik1 从 - 1 868pA± 1 88pA增加到 - 2 393pA± 367pA(刺激电压 - 1 2 0mV ,n=1 0 ,P <0 .0 1 ) ;③哇巴因 5μmol/L可增加大鼠心室肌细胞瞬时外向钾电流 ,使Ito从 1 2 73pA± 31 8pA增加到 1 70 7pA± 486pA(刺激电压 +60mV ,n =5 ,P <0 .0 1 )。结论 哇巴因诱发室性心律失常可能与它缩短心室肌细胞动作电位时程有关 ,而Ito的增加使二期平台期缩短 ,Ik1 的增加使三期复极加快 ,均参与了动作电位时程缩短的过程。同时增加Ik1 将影响静息膜电位 ,可能使膜反应性增强  相似文献   

11.
FOR anesthesiologis s ,treatingpostoperativepainhas alwaysbeen a problem.Althoughopioidshave been provedtobe effective,theirsideeffectscouldnotbeignored.With thedevelopmentofscienceand pharmacology,many drugs with aspectsof satisfactoryanalgesicefficacyand couldbe welltoleratedby patientshave been developed.And lornoxicamisone of them, which isa non-steroidalanti-inflammatorydrug (NSAID ), with analgesic, anti-infl-ammatory,andantipyreticproperties.Itseliminationhalf-time(3 to 5 hours) isle…  相似文献   

12.
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   

13.
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   

14.
Shock wave lithotripsy (SWL) is a treatment of choice for upper urinary stones. However, this procedure is inappropriate for obese patients because the focus is often unable to reach the target owing to the limited focal distance in shock wave source. Although treating such patients in a blast path may increase the application length of shock wave source, it's difficult to find this path on the lithotripter monitor. For this reason, we invented an adjustable calibration marker in order to set an effective focus in the shock wave hath.  相似文献   

15.
Excess production of reactive oxygen species(ROS)of mitochondrion mediated by hyperglycemia is the common pathogenesis of angiopathic complications of diabetes.TCM holds that the damp from the dysfunction of spleen.kidney and liver is the causative factor of complications of diabetes.This is similar to the mechanism of Ros resulting in angiopathic complications of diabetes.When the angiopathic complications of type II diabetes mellitus(T2DM)are difierentiated as caused by turbid damp in TCM can be explained as ROS.Since the obstruction of pathogenic damp in channels and collaterals is said to be the main pathogenesis,the treating principle should be dissolving the damp to remove the obstruction.  相似文献   

16.
INTRODUCTION Obesity is a complex emergent problem, which can be possibly solved not only by the diet but also by the life style and promotion of a constant physical exercise. 1, 2 No doubt careful attentions must be given to the nutritional condition of obese people, the dietary habits, the somatic build (i.e. distribution of fat mass) and the organic functions linked to formation of the fat mass. All the parameters should be constantly monitored before, during and after a diet treatment. 3, 4, 5  相似文献   

17.
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   

18.
People with dysglycemia are at high risk for atherosclerotic diseases. This study aims at investigating the atherosclerotic vascular damage in dysglycemia and its metabolic origin in Tibetan population.  相似文献   

19.
Objective: To observe the therapeutic effects in acupunture treatment of primary dysmenorrhea combined with spinal Tui Na, and study its mechanism. Methods: Thirty cases of the treatment group were treated by acupuncture combined with spinal Tui Na, and thirty cases in the control group were treated by routine acupuncture. Results: The total effective rate was 93.3% in the treatment group, and 73.3% in the control group, with a significant difference between the two groups (P<0.05). Conclusions: Acupuncture combined with spinal Tui Na has good prospects for treatment of primary dysmenorrhea.  相似文献   

20.
In treating chronic nephropathy,Luo Lingjie,a chief physician,pays attention to regulating the balance between yin and yang,treating infection if present,and removing pathogenic factors.He prescribes gentle drugs and uses carefully strongly warming-tonifying ones,emphasizes the importance of persuading the patient to persist in treatment with medication and nurse one's health for recuperation,and is good at combined use of TCM and western medicine therapy and brings the merits of various therapies into full play,with obvious theraoeutic effects.  相似文献   

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