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1.
目的:观察氨丁卡前列素对离体人子宫平滑肌收缩频率及幅度的影响,为临床合理使用提供参考。方法:制备离体人子宫平滑肌条蓄养于子宫肌蓄养液中,随机分为空白对照组和氨丁卡前列素用药组,使用张力换能器及BL-NewCentury系统分别测定两组子宫平滑肌条的收缩频率及幅度变化情况。结果:与空白对照组相比,氨丁卡前列素用药组子宫平滑肌条的收缩频率及幅度均有显著性增加(P<0.05)。结论:氨丁卡前列素可以增加离体人子宫平滑肌的收缩频率及幅度,临床合理使用可以促进子宫收缩,达到减少出血的目的。  相似文献   

2.
氨甲酰胆碱(CCh)可使事先以[^3H]花生四烯酸充分标记的CCL137细胞释放的花生四烯酸量明显增多,经CCh处理的CCL137细胞,其质膜中磷脂酶A2(PLA2)的活性明显增高:PLA2及其激活剂蜂毒肽都能像CCh处理一样,降低CCL137细胞与[^3H]NMS的结合作用;PLA2的非竞争性抑制剂米帕林能有效地减轻CCh所致细胞对[^3H]NMS结合的降低,以上结果表明,质膜中PLA2激活可能在CCh所致CCL137细胞的M-受体隐没中起重要作用,PLA2激活还与CCh所致CCL137细胞中磷脂酰肌醇代谢增强有关。  相似文献   

3.
目的探讨氨甲酰胆碱对完整动物心脏心室复极的影响。方法在4只绵羊冠状动脉回旋支内分别注入1.0 mol.L-1和2.5 mol.L-1的氨甲酰胆碱,注射时间3m in。记录回旋支支配区域心外膜心电图,测量心室的激动-恢复间期(AR I)以代表心室复极时间。静脉给予一氧化氮合成抑制剂(L-精氨酸20 mg.kg-1)后,再次冠脉内给予2.5 mol.L-1的氨甲酰胆碱。结果回旋支内灌注1.0 mol.L-1和2.5 mol.L-1的氨甲酰胆碱导致其支配区域心外膜心电图心室激动-恢复间期分别延长(38±17)m s和(58±14)m s(P<0.05)。氨甲酰胆碱所致的心室激动-恢复间期延长被L-精氨酸所阻断。结论冠脉内注射氨甲酰胆碱延长心室激动-恢复间期或心室复极时间,内源性一氧化氮很可能介导氨甲酰胆碱心室复极的影响。  相似文献   

4.
目的 研究前胡丙素对自发性高血压大鼠SHR及肾型高血压大鼠RHR的血管肥厚、细胞内钙、胶原、一氧化氮(NO)及血管反应性影响。方法 用显微测微仪测定血管中膜层,细胞大小,用Fura-2/AM为荧光指示剂,测定单细胞内[Ca^2 ]i,以测定羟脯氨酸含量反映胶原含量,用Griess法测定NO含量,以血管环观察收缩反应。结果 前胡丙素减轻血管中膜层增厚,维持细胞内[Ca^2 ]i稳态。减少胶原形成,增加SMCs释放NO。抑制血管环高反应状态。结论 前胡丙素抑制高血压血管肥厚,降低胶原含量及血管异常反应。  相似文献   

5.
目的 研究前胡丙素对自发性高血压大鼠SHR及肾型高血压大鼠RHR的血管肥厚、细胞内钙、胶原、NO及血管收缩的反应性影响。方法用显微测微仪测定血管中膜层厚度,细胞大小,用Fura-2/AM为荧光指示剂,测定单细胞内[Ca2+]i,以测定羟脯氨酸含量反映胶原含量,用Griess法测定NO含量,以血管环观察收缩反应。结果 前胡丙素抑制血管中膜层增厚,维持细胞内[Ca2+]i稳态。减少胶原形成,增加SMCs释放NO。抑制血管环高反应状态。结论 前胡丙素抑制高血压血管肥厚,降低胶原含量及血管异常反应。  相似文献   

6.
目的:比较氨甲酰胆碱和毛果芸香碱对血管内皮细胞M受体基因表达调节作用的异同点。方法:氨甲酰胆碱和毛果芸香碱分别孵育培养的牛主动脉内皮细胞10h后,提取细胞总RNA,RT-PCR方法测定M受体5个亚型mRNA的表达。结果:M_1~M_5受体mRNA在牛主动脉内皮细胞上均有表达,氨甲酰胆碱和毛果芸香碱孵育后表达量均增加,但二者之间无差异。结论:氨甲酰胆碱和毛果芸香碱对M受体5个亚型的基因表达均发生了相同的影响,两者对M受体可能的作用尚不能解释其对血管张力的影响。  相似文献   

7.
目的探讨滨蒿内酯(scoparone,Scop)对原代及短期传代培养的豚鼠气道平滑肌细胞(airway smooth musclecells,ASMCs)内钙的影响,同时,比较原代与传代ASMCs在形态、生长曲线及内钙释放受Scop及caffeine影响的异同。方法细胞计数法绘制原代及传代培养ASMCs的生长曲线,应用Fluo-3/AM为细胞内Ca2+示踪剂,通过倒置荧光纤维镜观察和记录原代及短期传代培养的ASMCs的细胞形态及其细胞内钙离子浓度([Ca2+]i)的改变。结果原代和传代培养ASMCs的倍增时间分别为(31.89±1.24)h和(22.91±6.82)h,传代培养ASMCs的倍增时间明显缩短(P<0.05),传代培养的ASMCs相对原代培养ASMCs体积增大。在细胞外液无钙条件下,不同浓度的Scop(10-6、10-5、10-4mol.L-1)可降低静息状态下培养的ASMCs的[Ca2+]i,并与给药浓度有关,原代与传代培养的ASMCs比较,对不同浓度的Scop的降钙反应无明显异同(P>0.05);不同浓度咖啡因(caffeine,10-4、10-3、10-2mol.L-1)在10-4mol.L-1Scop存在下,可升高ASMCs的[Ca2+]i,传代培养的ASMCs[Ca2+]i较原代对caffeine的反应下降(P<0.01)。结论Scop可降低培养的ASMCs的[Ca2+]i,并且不受细胞传代影响。短期传代培养的ASMCs相对于原代细胞,形态及内钙释放通道特性发生了改变。  相似文献   

8.
AIM: To study the effect of superoxide anion on the Ca2+ homeostasis in smooth muscle cells isolated from the rabbit pulmonary artery. METHODS: Intracellular Ca2+ concentration ([Ca2+]i) was investigated using cell suspension of freshly isolated smooth muscle cells from rabbit pulmonary artery (PASMC). Fura-2 fluorescent ratio obtained at 340 nm and 380 nm wave lengths was measured as an indicator of [Ca2+]i. RESULTS: ATP 30 mumol.L-1 induced a transient increase in the ratio (Ca2+ transient). Thapsigargin, an inhibitor of sarcoplasmic Ca2+ ATPase, induced a phasic increase in the ratio due to Ca2+ leak from intracellular store sites, but not the sustained increase, thereby suggesting the absence of Ca2+ release-activated Ca2+ entry (CRAC) mechanism in PASMC. When PASMC were exposed to superoxide anion by the pretreatment with xanthine and xanthine oxidase (X/XO) for 30 min, sustained component of ATP-induced Ca2+ transient was elevated. The ratios at 5 and 10 min after ATP application (delta ratio5 min and delta ratio10 min) were increased from 0.091 +/- 0.022 to 0.149 +/- 0.048 (P < 0.05) and from 0.021 +/- 0.020 to 0.117 +/- 0.047 (P < 0.01), respectively. But, thapsigargin-induced [Ca2+]i transient was not affected by X/XO. CONCLUSION: Superoxide anion makes ATP-induced Ca2+ transient sluggish, and does not affect Ca2+ leak pathway in PASMC.  相似文献   

9.
目的前胡丙素(Pra-C)对血管紧张素II(Ang II)致离体培养大鼠血管平滑肌细胞(SMCs)肥厚模型胞内游离钙浓度、NO含量和信号转导的影响。方法以Ang II刺激SMCs形成肥厚模型,用倒置显微镜测定SMCs面积;用Fura-2/AM测定单细胞内[Ca2+]i,Griess法测定NO含量;在PMA和ST(PKC激动剂及抑制剂)、PTX(Gi蛋白敏感毒素)作用下观察Pra-C对KCl和NE所致胞内[Ca2+]i浓度变化的影响。结果Pra-C组SMCs细胞面积较肥厚组减小39.01%,并接近正常细胞水平;NO含量明显增加;胞内[Ca2+]i对KCl和NE激动的反应明显低于肥厚组。PMA使肥厚SMCs[Ca2+]i升高,而ST及PTX则使之降低,Pra-C均使之恢复正常。结论Pra-C抑制Ang II致体外培养细胞SMCs肥厚,改善肥厚细胞因PKC和Gi蛋白的信号转导改变所致的[Ca2+]i改变。  相似文献   

10.
使用亲水性配基[~3H]NMS和亲脂性、膜通透性配基[~3H]QNB,证实氨甲酰胆碱(CCh)所致CCL137细胞中mAChR的减少,可分为两个不同的阶段。第一阶段的特点是完整细胞膜表面上[3~H]NMS的结合部位明显减少,它与CCh的作用时间和用量有关;但对[~3H]QNB的结合没有明显影响;在除去CCh后,不需蛋白质重新合成这种变化即可恢复至正常,故认为该阶段属受体隐没或内移。第二阶段的特点是完整细胞对该二配基的结合均告降低,欲使这种变化恢复正常,需要更长的时间,并需有蛋白质重新合成,故认为该阶段为内移的受体降解或下行调节。  相似文献   

11.
目的:检测乙酰胆碱(acetylcholine,ACh)对人妊娠与未妊娠子宫颈平滑肌细胞生物合成肌醇1,4,5三磷酸(inositol 1,4,5-triphosphate,IP_3)的影响。方法:[~3H]IP_3竞争性蛋白结合实验。结果:基础状态下妊娠与未妊娠子宫颈平滑肌IP_3水平分别为(82±9)和(96±10)nmol·g~(-1)(protein)。ACh 50μmol·L~(-1)孵育5min时IP_3水平达峰,分别为(109±11)和(122±15)nmol·g~(-1)(protein),但对妊娠与未妊娠时的作用差异不显著。阿托品(Atr)1μmol·L~(-1)抑制ACh促IP_3生成作用。结论:基础状态时的妊娠妇女子宫颈平滑肌细胞IP_3水平高于未妊娠妇女,ACh促进子宫颈平滑肌细胞IP_3合成。  相似文献   

12.
用荧光分光光度法及同位素放射免疫分析法检测丙泊酚(30-300μmol·L-1)影响大鼠肺动脉平滑肌细胞(PASMC)内游离钙离子浓度([Ca2+]i)与肌醇-1,4,5-三磷酸(IP3)合成作用,以探讨丙泊酚舒张肺动脉平滑肌的作用机理.结果表明,与丙泊酚共同培养72h,对PASMC[Ca2+]i基础水平无明显影响,但可浓度依赖性抑制去甲肾上腺素(NE3μmol·L-1)引起的[Ca2+]i升高作用;当细胞外液无钙或存在钙通道阻滞剂维拉帕米(30μmol·L-1)时,丙泊酚抑制NE升高[Ca2+]i作用被增强;丙泊酚还可浓度依赖性抑制NE促进IP3合成作用.结果提示丙泊酚舒张血管平滑肌作用与抑制IP3介导的细胞内钙释放密切相关.  相似文献   

13.
目的:研究5HT对ADP介导的血小板聚集反应的增强作用.方法:以透光法、图像法和受体结合法评价聚集反应、单细胞内钙和三磷酸肌醇的含量.结果:5HT(003-3μmol·L-1)浓度依赖性地引起PRP的透光度降低(DLT),电镜结果显示血小板变形的同时伴有颗粒中心化,无聚集和释放反应.Fura2负载后,5HT升高[Ca2+]i,90秒达峰值,IP3一过性升高.ADP同样引起DLT,但可被5HT消除,呈浓度依赖性.ADP的聚集反应和[Ca2+]i动员则由于5HT预处理而升高.结论:5HT增强ADP的聚集反应与5HT的细胞内钙动员及ADP的外钙内流两者的叠加作用有关.  相似文献   

14.
INTRODUCTION Circulation hypotension induced by hemorrhagicshock is one of the main causes of death after severewounds or trauma. When the hemorrhagic shock hasdeveloped to a decompensatory stage, it is difficult toreverse the hypotension using usual vasoconstrictor,such as norepinephrine. One of the explanations ofhypotension is due to the hyposensitivity of arterialsmooth muscle cells (SMC) to vascular constrictorstimuli[1,2]. Previous studies showed that the vascularhyporesponse was r…  相似文献   

15.
目的分析肺动脉高压时肺动脉平滑肌细胞Ryanod-ine受体[Ca2+]i释放功能的改变。方法腹腔注射野百合碱建立大鼠肺动脉高压模型,原代培养肺动脉平滑肌细胞,Fura-2/AM负载培养细胞,荧光测钙技术测量Ryanodine受体激动剂对[Ca2+]i变化的影响。结果10nmol.L-1Ry-anodine使对照组[Ca2+]i平均增加(93.31±12.41)nmol.L-1,使PAH组[Ca2+]i平均增加(141.71±13.59)nmol.L-1。两组样本[Ca2+]i增加的数值差异有显著性(P<0.01);10mmol.L-1Caffine使对照组[Ca2+]i平均增加(149.02±13.02)nmol.L-1,使PAH大鼠PASMC的[Ca2+]i平均增加(191.2±21.26)nmol.L-1,两组样本[Ca2+]i数值的变化差异有显著性(P<0.01)。结论肺动脉高压大鼠原代培养的肺动脉平滑肌细胞对Ryanodine受体激动剂的敏感性增强,提示肺动脉高压时Ryanodine受体释放[Ca2+]i的功能发生了异常改变。  相似文献   

16.
Tricyclic antidepressants (TCA) have been clinically prescribed in the auxiliary treatment of cancer patients. Although protriptyline, a type of TCA, was used primarily in the clinical treatment of mood disorders in cancer patients, the effect of protriptyline on physiology in human osteosarcoma is unknown. This study examined the effect of protriptyline on cytosolic free Ca2+?concentrations ([Ca2+]i) and viability in MG63 human osteosarcoma cells. Protriptyline between 50 and 250?μM evoked [Ca2+]i rises concentration-dependently. Protriptyline induced influx of Mn2+, indirectly implicating Ca2+?influx. Protriptyline-evoked Ca2+?entry was inhibited by nifedipine by 20% but was not altered by econazole, SKF96365, GF109203X, and phorbol-12-myristate-13-acetate (PMA). In Ca2+-free medium, treatment with protriptyline inhibited the endoplasmic reticulum Ca2+?pump inhibitor thapsigargin-evoked [Ca2+]i rises. Conversely, treatment with thapsigargin inhibited 45% of protriptyline-evoked [Ca2+]i rises. Inhibition of phospholipase C (PLC) with U73122 failed to alter protriptyline-evoked [Ca2+]i rises. Protriptyline at 50–250?μM decreased cell viability, which was not reversed by pretreatment with the Ca2+?chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Collectively, our data suggest that in MG63 cells, protriptyline induced [Ca2+]i rises by evoking Ca2+?release from the endoplasmic reticulum and other stores in a PLC-independent manner, and Ca2+?entry via a nifedipine-sensitive Ca2+?pathway. Protriptyline also caused Ca2+-independent cell death.  相似文献   

17.
  1. Cytosolic calcium concentration ([Ca2+]i) by indo 1 microspectrofluorimetry in freshly isolated cells and isometric contraction of isolated rings were measured in response to muscarinic cholinoceptor stimulation in rat tracheal smooth muscle.
  2. In isolated myocytes, acetylcholine (ACh, 0.031 μM) caused a rapid and graded increase in [Ca2+]i up to a net amplitude of 492±26 nM (n=19) which gradually declined. The EC50 for ACh was 0.13 μM. This first [Ca2+]i peak was followed, when the ACh concentration increased, in approximately 5060% of the cells, by successive peaks of decreased amplitude ([Ca2+]i oscillations) superimposed on the plateau phase. Whereas the percentage of cells exhibiting [Ca2+]i oscillations remained consistent, the frequency of these oscillations increased to up to 10 min−1 with an ACh concentration of 100 μM.
  3. Removal of extracellular calcium (in the presence of EGTA, 0.4 mM) or addition of the voltage-dependent Ca2+-channel blocker verapamil (10 μM) did not alter the first [Ca2+]i peak, the plateau or the oscillations induced by ACh or carbachol. In contrast, the specific inhibitor of the sarcoplasmic Ca2+-ATPase, thapsigargin (1 μM), completely abolished the [Ca2+]i response. Thapsigargin (1 μM) also blocked the caffeine (5 mM)-induced transient rise in [Ca2+]i.
  4. Atropine (a non-selective muscarinic cholinoceptor antagonist) and 4-diphenyl acetoxy N-methyl piperidine (4-DAMP, a selective M3 antagonist) inhibited the [Ca2+]i response to muscarinic cholinoceptor activation with an IC50 of 13 and 20 nM, respectively. Pirenzepine (a selective M1 antagonist) also totally inhibited the [Ca2+]i response to ACh but with a higher IC50 of 2 μM. Methoctramine (a selective M2 antagonist) up to a concentration of 10 μM caused only a 40% inhibition. The effect of muscarinic antagonists on cumulative concentration-response curves (CCRC) for carbachol was assessed at the following concentrations: atropine and 4-DAMP at 3, 10 and 30 nM; pirenzepine 0.3, 1 and 3 μM, and methoctramine at 1, 3 and 10 μM. For these concentrations, all of the antagonists produced a rightward shift of the CCRC for carbachol and pA2 values were 9.2, 8.8, 6.7 and 6.3, respectively.
  5. In conclusion, the present study indicates that muscarinic stimulation of rat isolated tracheal smooth muscle cells induces [Ca2+]i oscillations. The occurrence of these oscillations depends on the graded amplitude of the first [Ca2+]i rise and their frequency may play a role in the amplitude of the mechanical activity in response to muscarinic cholinoceptor activation. Both the [Ca2+]i and the contractile responses are primarily dependent on activation of the M3 receptor subtype.
  相似文献   

18.
Smoking increases the risk of cardiovascular disorders and leads to damage caused by inflammation and oxidative stress. The actin cytoskeleton is a key player in the response to inflammatory stimuli and is an early target of cellular oxidative stress. The purpose of this study was to investigate the changes in actin cytoskeleton dynamics in human endothelial EA.hy926 cells exposed to cigarette smoke extract (CSE). Immunostaining revealed that CSE exposure resulted in modification of the actin cytoskeleton and led to cell rounding in a dose‐ and time‐dependent manner. In addition, the intracellular calcium concentration was increased by treatment with CSE. Pretreatment with antioxidants (lipoic acid, glutathione, N‐acetyl cysteine, aminoguanidine, α‐tocopherol, and vitamin C) significantly attenuated the CSE‐induced actin cytoskeleton reorganization and cell rounding. Calcium ion chelators (EGTA, BAPTA‐AM AM) and a potent store‐operated calcium channel inhibitor (MRS 1845) also reduced CSE‐induced intracellular calcium changes and attenuated actin cytoskeleton reorganization and cell morphology change. Moreover, the CSE‐induced intracellular calcium increase was suppressed by pretreatment with the inositol trisphosphate receptor (IP3R) inhibitor xestospongin C, the phospholipase C (PLC) inhibitor U‐73122, and the protein kinase C (PKC) inhibitor GF109203X. These results suggest that reactive oxygen species production and intracellular calcium increase play an essential role in CSE‐induced actin disorganization and cell rounding through a PLC–IP3–PKC signaling pathway. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1293–1306, 2016.  相似文献   

19.
1. The aim of the present investigation was to contrast the Ca2+ dependence of cardiac energy metabolism in two species with differential reliance on extracellular Ca2+ for excitation-contraction coupling. 2. We measured energy expenditure as the rate of oxygen consumption (Vo2) of isolated, Langendorff-perfused hearts of rats and guinea-pigs during KCl arrest. In parallel experiments, we indexed intracellular Ca2+ concentration ([Ca2+]i) of isolated right-ventricular trabeculae, using the Ca2+ fluorophore fura-2 and ratiometric spectrofluorometry. By varying extracellular Na+ concentration ([Na+]o), Vo2-[Na+]o and [Ca2+]i-[Na+]o relationships were constructed for each species. 3. Reduction of [Na+]o during K+ arrest caused pronounced species-dependent elevations of both Vo2 and [Ca2+]i. Despite the species dependence of both Vo2 and [Ca2+]i on [Na+]o, a single species-independent Vo2-[Ca2+]i relationship obtained. 4. We infer that elevation of the metabolic rate of the arrested heart above its basal value is determined primarily by [Ca2+]i and is not species dependent.  相似文献   

20.
目的:探讨1-甲基-5-(4-二甲氨基苄烯)-5H-茚[1,2b]吡啶三氟甲磺酸盐(受试物)对人喉表皮样肿瘤细胞HEp-2的增殖抑制和凋亡诱导作用。方法:采用MTT法观察受试物对HEp-2增殖的抑制作用,Hoechst 33258荧光染色观察HEp-2细胞凋亡形态学变化,流式细胞仪PI单染法检测细胞周期及凋亡率,采用Western Blot分析检测促凋亡蛋白Bid的表达。结果:1-甲基-5-(4-二甲氨基苄烯)-5H-茚[1,2b]吡啶三氟甲磺酸盐可抑制HEp-2细胞的增殖,并呈时间和剂量依赖性;用受试物(4μmol.L-1)处理细胞(24和48 h),经Hoechst 33258荧光染色,可见细胞凋亡形态学改变;流式细胞仪检测显示,HEp-2细胞周期发生改变,凋亡率增加;Western Blot分析结果显示,受试物可使促凋亡蛋白Bid表达水平上升。结论:1-甲基-5-(4-二甲氨基苄烯)-5H-茚[1,2b]吡啶三氟甲磺酸盐可抑制HEp-2细胞增殖,诱导其凋亡。  相似文献   

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