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1.
齐墩果酸对谷氨酸诱导神经细胞损伤的影响   总被引:4,自引:0,他引:4  
目的 研究齐墩果酸(oleanolie acid,OA)对谷氨酸诱导大鼠海马神经元损伤的影响.方法 选用新生Wistar大鼠原代培养海马神经元,建立谷氨酸细胞毒性模型,借助于共聚焦显微镜结合钙荧光指示剂Fluo-3-AM观察OA对海马神经元[Ca2 ]i的影响.结果 1、10、100 μmol/L OA 谷氨酸组细胞内[Ca2 ]i均明显下降,与谷氨酸对照组相比[Ca2 ]i分别降低了0.32±0.05,0.41±0.06和0.43±0.09,差异均有显著性(P<0.05).结论 OA可以降低谷氨酸诱导海马神经元[Ca2 ]i升高,对谷氨酸诱导的海马神经元损伤有一定的保护作用.  相似文献   

2.
吗啡对大鼠培养海马神经元钙离子作用机制的研究   总被引:3,自引:1,他引:2  
目的 研究吗啡对海马神经元游离子浓度([Ca^2 ]i)影响的机制,探索吗啡成瘾的神经生物学机制及对吗啡成瘾可能的治疗途径。方法 运用新型荧光探针Fluo-4 , 利用激光共聚焦显微镜研究吗啡对大鼠培养海马神经元[Ca^2 ]i作用机制。结果 10μmol/L吗啡急性刺激引起海马神经元[Ca^2 ]i升高,μ阿片受体选择性拮抗剂CTOP(1μmol/L)不能阻断吗啡引起的细胞内[Ca^2 ]i增加,δ2阿片受体选择性拮抗剂Naltrindole(1μmol/L)阻断了吗啡引起的细胞内[Ca^2 ]i反应,特异性的内质网钙泵抑制剂Thapsigargin(TG,1μmol/L)预处理海马神经元组断吗啡引起的细胞内[Ca^2 ]i增加,L-钙通道阻断剂Verapamil(20μmol/L)预处理海马神经元不能完全抑制吗啡引起的细胞内[Ca^2 ]i增加;100μmol/L吗啡长时程(24h)作用于海马神经元,细胞内[Ca^2 ]i升高,加入10μmol/L纳络酮急性戒断后,不能阻断细胞内[Ca^2 ]i升高,反而引起[Ca^2 ]i异常升高。结论 吗啡急性刺激引起的海马神经元内钙增加主要来源于δ2阿片受体介导的IP3敏感的钙库释放。  相似文献   

3.
目的:观察睫状神经营养因子(CNTF)对内质网钙泵特异性抑制剂毒胡萝卜素(thapsigargin,Tg)引起海马神经元内胞质游离Ca2 浓度([Ca2 ]i)升高的抑制作用.方法:出生24 h以内SD大鼠海马神经元原代培养10~14 d备用,以活细胞内荧光探针Frua2/AM 实时检测[Ca2 ]i.实验分3组:A组(n=20),EGTA(3 mmol/L);B组(n=40),EGTA(3 mmol/L) Tg(10 μmol/L);C组(n=12),EGTA(3 mmol/L) Tg(10 μmol/L) CNTF(500 U/μl).结果:用足量EGTA螯合细胞外Ca2 后,测得[Ca2 ]i≤(30.73±7.25) nmol/L;加入EGTA Tg后,[Ca2 ]i显著升高([Ca2 ]i≥[91.55±12.24] nmol/L);加入EGTA Tg CNTF后,升高的[Ca2 ]i明显降低([Ca2 ]i≤[26.09±7.16] nmol/L,P<0.01).结论:CNTF可明显减弱Tg的钙库质膜钙泵抑制作用,使胞质[Ca2 ]i降低.提示CNTF通过增加胞内钙库对细胞内游离Ca2 的吸收作用来降低海马神经元的Ca2 负荷.  相似文献   

4.
目的探讨普罗托品(protopine, Pro)对大鼠血管平滑肌细胞内游离钙浓度的影响.方法采用无Ca2 -复Ca2 的实验法,间接观察Pro对大鼠血管平滑肌细胞内游离钙浓度([Ca2 ]i)的可能影响,再利用钙荧光指示剂Fura-2/AM负载的培养大鼠胸主动脉平滑肌细胞,直接观察在Pro存在下,对去甲肾上腺素(NA)和高钾所致的 [Ca2 ]i的升高的影响.结果在无钙Krebs液中,Pro 10、30、100 μmol/L对NA所致血管条的短暂收缩均有明显的浓度依赖性抑制作用,对复Ca2 后NA所诱发的持续收缩也呈剂量依赖性抑制作用.在Fura-2/AM负载血管平滑肌细胞的实验表明,Pro (50 μmol/L, 100 μmol/L) 对静息时的 [Ca2 ]i无明显影响;在有外钙存在条件下,Pro 50 μmol/L能明显降低NA所致[Ca2 ]i的升高,对KCl引起的 [Ca2 ]i 升高有降低趋势;当Pro的浓度增加到100 μmol/L时,对NA和KCl引起的 [Ca2 ]i升高均有明显的抑制作用.结论 Pro可能通过抑制Ca2 释放和(或)Ca2 内流来降低NA和高钾所致血管平滑肌[Ca2 ]i的升高,从而抑制血管平滑肌的收缩反应.  相似文献   

5.
Na+,K+-ATP酶参与缺氧所致大鼠皮质神经元内钙升高   总被引:3,自引:0,他引:3  
目的:探讨Na ,K -ATP酶对缺氧所致大鼠皮质神经元内钙升高的影响.方法:采用激光共聚焦显微镜及可视化动缘探测系统,测定培养大鼠皮质神经元在缺氧不同时间和双氢哇巴因(DHO,一种Na -K -ATP酶抑制剂)不同浓度时细胞内钙离子浓度([Ca2 ]i)和细胞内钠离子浓度([Na ]i),并观察DHO对缺氧后神经元[Ca2 ]i和[Na ]i升高作用的影响.结果:DHO(10-9~10-3mol/L)和缺氧(4~20 min)均可显著升高正常皮质神经元[Ca2 ]i和[Na ]i,并分别具有剂量依赖性和时间依赖性.在缺氧4 min时皮质神经元[Ca2 ]i和[Na ]i即明显升高,此时给予DHO 10-3mol/L可使二者进一步升高;但当皮质神经元缺氧15 min后,再给予相同剂量的DHO则不能使[Ca2 ]i和[Na ]i进一步增加;若对DHO(10-3mol/L)预先升高[Ca2 ]i的正常神经元再进行缺氧灌流,则[Ca2 ]i不继续升高.结论: Na ,K -ATP酶抑制是缺氧所致大鼠皮质神经元[Ca2 ]i升高的机制之一.  相似文献   

6.
地塞米松快速抑制大鼠背根神经节细胞中ATP所致的钙升高   总被引:1,自引:1,他引:0  
目的 通过观察地塞米松对大鼠背根节神经元中ATP所致的细胞内游离钙离子浓度(intracellular calcium concentration,[ca2+]i)升高的影响,了解糖皮质激素是否通过非基因组作用影响初级感觉神经元的兴奋性.方法 分离、培养大鼠背根神经节细胞,采用激光共聚焦技术观察地塞米松对培养神经元ATP所致的[Ca2+]i升高的影响.结果 ATP(100 μmol/L)可导致背根节神经元[Ca2+]i升高,是由P2X受体介导细胞外Ca2+内流所致;地寨米松预孵育5 min可剂量依赖性地抑制背根节神经元ATP所致的[Ca2+]i升高,地塞米松的抑制作用可被糖皮质激素受体拮抗剂RU38486(10 μmol/L)、蛋白激酶A抑制剂H-89(10 μmol/L)所阻断.结论 地塞米松通过糖皮质激素受体激活细胞内蛋白激酶A信号途径可显著抑制大鼠背根节神经元ATP所致的[Ca2+]i升高.糖皮质激素可通过非基因组作用影响初级感觉神经元的ATP/P2X受体功能而参与痛觉的调制.  相似文献   

7.
目的 :探讨铅对大鼠海马神经元 Ca2 浓度的影响及其与长时程增强 (L TP)的关系。方法 :断乳后 Wistar大鼠自由饮用不同浓度醋酸铅溶液 (0 .0 15 % ,0 .10 % ,0 .15 % ) ,建立慢性染铅动物模型。高频刺激 (HFS)海马区诱发长时程变化后 ,分离海马神经元 ,测定 [Ca2 ]i。结果 :各染铅组大鼠海马神经元 [Ca2 ]i与对照组比较均明显增高(P <0 .0 5 ) ;血铅浓度 (3.2 8± 0 .88) μm ol/ L 以上时海马 L TP产生率下降 ,三染铅组 PS幅值均降低 ,L TP阴性组 [Ca2 ]i 明显高于 L TP阳性组 (P <0 .0 5 )。结论 :慢性染铅可使 HFS后大鼠海马神经元 [Ca2 ]i 升高 ,损害海马区 L TP的在体诱导 ;铅致 L TP发生率下降与海马神经元 [Ca2 ]i 增高有关  相似文献   

8.
目的探讨三磷酸腺苷(ATP)对三叉神经痛大鼠感觉神经元内钙离子浓度([Ca2+]i)的影响及其信号转导机制。方法 SD大鼠眶下神经缩窄造成三叉神经痛模型,造模后1周处死大鼠,取出三叉神经节(TG),分离出完整的小直径神经元(﹤600μm2)用于钙离子成像,通过使用荧光染料来标记相关激动剂,检测毒胡萝卜内酯(Tg,1μmol/L)、咖啡因(Caff,20 mmol/L)和ATP(100μmol/L)作用下TG小直径神经元内[Ca2+]i变化。结果①在正常外液和无钙外液中,在大鼠TG小直径神经元上分别给予Tg、Caff和ATP均能够引起[Ca2+]i不同程度升高;②在无钙外液中,ATP引起的TG神经元[Ca2+]i升高可被Tg可逆性地抑制(n=8,P<0.01);③在无钙外液中,ATP引起的TG神经元[Ca2+]i升高可被P2受体阻断剂苏拉明(suramin,100μmol/L)明显抑制;④在正常外液中,Tg引起TG神经元[Ca2+]i升高,当升高达到最大后再次给予ATP,仍然能引起[Ca2+]i进一步升高。结论在大鼠TG神经元中同时存在IP3敏感钙库和ryanodine敏感钙库。ATP可通过两种途径引起细胞内[Ca2+]i升高,一种途径是激动P2Y受体引起IP3敏感钙库的Ca2+释放,另一种途径是激动P2X受体引起细胞外Ca2+内流。在无钙外液中,ATP引起的TG神经元[Ca2+]i升高是通过IP3敏感钙库释放引起的。  相似文献   

9.
目的探讨介导Ca2+池操纵性Ca2+内流的Ca2+通道特性. 方法以Fura-2荧光探针测定细胞质游离Ca2+浓度([Ca2+]i). 结果 (1)10 μmol/L环匹阿尼酸(CPA)可触发大鼠主动脉平滑肌细胞[Ca2+]i的双相升高(峰值和持续相).(2)SK&F96365(5~40 μmol/L)以浓度依赖性抑制CPA触发的[Ca2+]i升高持续相.(3)1 μmol/L硝苯地平阻断电压依赖性Ca2+通道后,20 μmol/L SK&F96365仍能抑制CPA触发的[Ca2+]i升高持续相;而在20 μmol/L SK&F96365抑制CPA触发[Ca2+]i升高持续相后,1 μmol/L硝苯地平不能产生进一步的抑制作用. 结论电压依赖性Ca2+通道和Ca2+池操纵性Ca2+通道介导了Ca2+池操纵性Ca2+内流.  相似文献   

10.
目的探讨柴胡皂苷元D (Saikogenin D, SGD)对C6大鼠神经胶质瘤细胞内游离Ca2 浓度[Ca2 ]i的影响.方法采用 Fura-2/AM荧光指示剂测定SGD引起的C6大鼠神经胶质瘤细胞[Ca2 ]i变化.结果 SGD(1×10-5~1×10-4 mol/L)剂量依赖性地升高[Ca2 ]i,其EC50为3.5×10-5 mol/L.SGD的升高[Ca2 ]i作用被Thapsigargin显著降低.2-aminoethoxydiphenylborate (2-APB, 1×10-4 mol/L) 和 U73122 (2×10-6 mol/L)显著降低组胺的升高[Ca2 ]i作用,但对SGD的升高[Ca2 ]i作用无影响.咖啡因和阿诺碱不影响SGD升高[Ca2 ]i.结论 SGD通过独立于肌醇三磷酸(IP3)受体系统和阿诺碱受体系统的机制,引起细胞内钙释放,导致[Ca2 ]i升高.  相似文献   

11.
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   

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.
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   

15.
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   

16.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

17.
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   

18.
Journal of Nanjing Medical University (English Edition) JNMU, sponsored by Nanjing Medical University, was established in 1987. It is a bimonthly comprehensive English medical journal published locally and abroad.Since 2007, Journal of Nanjing Medical University (English Edition )was granted Elsevier the full publishing and distribution rights worldwide for the Electronic Edition, excluding the People's Republic of China.  相似文献   

19.
Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.  相似文献   

20.
ANTI-PROLIFERATION EFFECT OF ORIDONIN ON HL-60 CELLS AND ITS MECHANISM   总被引:4,自引:0,他引:4  
Objcetive To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.  相似文献   

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