Relationship of Intracellular Free Ca^2＋ Concentration and Calcium-activated Chloride Channels of Pulmonary Artery Smooth Muscle Cells in Rats under Hypoxic Conditions

Hypoxic pul monary hypertension ( HPH) ischaracterized by an elevation of pul monary vascularreaction and pul monary vascular reconstruction.Cytoplasmic free Ca2 concentration ([ Ca2 ]i)plays a key role in the regulation of vascular tone ,pul monary vasoconstriction and proliferation ofsmooth muscle cells[1]. The present study evalua-ted the role of [Ca2 ]iin the regulation of pul mo-nary vascular tone through regulation of calcium-activated chloride (Clca) channels in rats under a-cute h…     

Effect of SJAMP on human platelet cytoplasmic Ca2+

Summary Using the method of dual-wavelength measurement of platelet [Ca²⁺]_i and Fura-2 as the Ca²⁺ fluorophore probe, we measured the effect of acidic Mucopolysaccharide fromSticopus Japonicus Selenka (SJAMP) on platelet [Ca²⁺]_i. The results showed that the most significant increase in platelets [Ca²⁺]_i was seen when the concentration of SJAMP was 100μg/ml and the elevation of normal platelet [Ca²⁺]_i was 93.96 ± 10.24 nmol/L (n=10). In the presence of extracellular Ca²⁺ (1 mmol/L), the magnitude of platelet [Ca²⁺]_i response to SJAMP was increased and the [Ca²⁺]_i could reach 116.72±10. 66 nmol/L (n = 10). On the other hand, the magnitude of increased platelet [Ca²⁺]_i induced by SJAMP was smaller and the duration of [Ca²⁺]_i reaching the highest level was longer when compared with other platelet aggregation agents. In the mean time, if platelets were first incubated with cyclooxygenase inhibitor, the rise of [Ca²⁺]_i evoked by SJAMP was inhibited. The results indicated that the mechanism of the rise of [Ca²⁺]_i induced by SJAMP might be dependent upon the generation of prostaglandin endoperoxides and(or) TXA₂. This project was supported by grant from the National Nature Science Foundation of China (No. 39370322).     

Effects of calcium-activated chloride channels on proliferation of pulmonary artery smooth muscle cells in rats under chronic hypoxic condition

Objective: To investigate the effects of calcium-activated chloride (C1Ca) channels on proliferation of pulmonary artery smooth muscle cells(PASMCs) in rats under chronic hypoxic condition. Methods:The cultured PASMCs were placed under normoxic and chronic hypoxic conditions:The cells were observed by light and electron microscope; The cell cycles were observed by flow-cytometry; Immunocytochemistry staining was used to detect the expressions of PCNA, c-los and c-jun of PASMCs; Cytoplasmic free Ca2 con-centration ([Ca2 ]) in PASMCs was investigated by fluorescent quantitation using fluorospectrophotometer. Results:The PASMCs were contractile phenotype under normoxic conditions. Observation by transmission electron microscope: In kytoplasm of contractile phenotype cells, myofilament bundles were abundant and the content of cell organs such as Golgi's bodies were rare. The PASMCs were synthetic phenotype under chronic hypoxic condition. There were inereased free ribosomes, dilated rough endoplasmic reticulums, highly developed Golgi complexes, decreased or disappeared thick filaments and dense body in kytoplasm of synthetic phenotype cells. After NFA and IAA-94, the situations were reversed The number of S4,GzM PASMCs were significantly increased in chronic hypoxic condition; The NFA and IAA-94 were shown to significantly decrease them from (28.6±1.0)% to (16.0±1.6)% and the number of G0G1 PASMCs significantly increased from (71.4 ±1.9)% to (83.9±1.6)% (P＜ 0.01). In chronic hypoxic conditions, the expression of proliferating cell nucleus antigen was significantly increased; The NFA and IAA-94 were shown to significantly decrease it from (81±6)% to (27±7)%(P＜0.01). The expression of c-los and c-jun were significantly increased in-chronic hypoxic conditions; The NFA and IAA-94 were shown to significantly decrease them from 0.15 ± 0.02, 0.32 ± 0.05 to 0.05 ± 0.01, 0.12±0.05, respectively (P＜ 0.01); Under chronic hypoxic conditions, [Ca2 ]. Was increased; The NFA and IAA-94 decreased it from (281.8±16.5)nmol/L to (117.7±15.4)nmol/L(P＜0.01). Conclusion:Hypoxia initiated the change of PASMCs from contractile to synthetic phenotype and increased proliferation of PASMCs. NFA and IAA-94 depressed cell proliferation by blocking C1Ca channels in hypoxic condition. These may play an important role in proliferation of PASMCs under chronic hypoxic conditions.     

慢性低氧钙激活氯通道在大鼠肺动脉平滑肌细胞增殖中的作用

目的探讨慢性低氧时钙激活氯通道（ClCa）在大鼠肺动脉平滑肌细胞（PASMCs）增殖中的作用。方法将PASMCs分别置于常氧及慢性低氧下,采用形态学、流式细胞术、免疫细胞化学法,观察ClCa阻滞剂尼氟灭酸（NFA）和indaryloxyacetic acid（IAA-94）对PASMCs增殖的影响。结果慢性低氧：①PASMCs呈合成表型,而常氧为收缩表型,NFA和IAA-94干预后呈合成表型的PASMCs向收缩型转变;②S＋G2M期细胞所占比例增高,NFA和IAA-94干预后减低,且G0G1期细胞所占比例增加（P〈0.01）;③PCNA表达阳性率增高,NFA和IAA-94干预后降低（P〈0.01）;④c-fos和c-jun蛋白阳性染色A增高,NFA和IAA-94干预后降低（P〈0.01）。结论慢性低氧引起细胞表型改变,可促进细胞增殖,而抑制ClCa的活性可抑制细胞的增殖,提示ClCa参与了低氧PASMCs的增殖。     

2-甲基-3-羟基蒽醌诱导人乳腺癌MCF-7细胞凋亡的机制

为探讨2-甲基-3-羟基蒽醌抗肿瘤作用及其机制,本研究采用锥虫蓝法检测细胞活力,流式细胞仪检测细胞周期变化、细胞凋亡率、线粒体膜电位及细胞内游离钙的变化,Western blot方法检测凋亡相关蛋白caspase-4、caspase-7、caspase-9、Bcl-2、Bax、JNK、细胞色素C的表达。结果发现：2-甲基-3-羟基蒽醌时间依赖性地抑制乳腺癌细胞的生长,升高细胞内游离钙含量,降低线粒体膜电位并诱导其凋亡;药物上调Bax并下调Bcl-2蛋白的表达;诱导caspase-4、caspase-7、caspase-9、calpain的活化及细胞色素C的释放。结果提示2-甲基-3-羟基蒽醌可能通过Ca²⁺/calpain/caspase-4途径诱导人乳腺癌MCF-7细胞凋亡。     

Hypoxia increases cytosolic free calcium in porcine pulmonary arterial endothelial cells

Summary Alteration of cytosolic free calcium ([Ca²⁺ ₁]) in hypoxia was studied with fluorescent probe, Fura-2 in cultured porcine pulmonary arterial endothelial cells. It was found that hypoxia caused by bubbling the cell suspension with 100% N₂ increased [Ca²⁺ ₂] in endothelial cells by 90±20% (n=8,P<0.05), but didn’t affect that in a Ca²⁺-free buffer, La³⁺ (2×10⁻⁵ mol/L) inhibited the hypoxia-induced increment in [Ca²⁺]₁, whereas verapamil (10⁻⁸ mol/L) didn’t. These findings suggest that hypoxia could induce Ca²⁺ influx in pulmonary arterial endochelial cells, which might play an important role in vascular response to hypoxia.     

Effects of cyclosporine A on angiotensin II-induced cardiomyocyte hypertrophy in neonatal rats

Summary The effects of cyclosporine A (CsA) on Angiontensin II (Ang II)-induced protein contents, c-fos protein levels and cytosolic Ca²⁺ level ([Ca²⁺]i) in cultured cardiomyocytes of neonatal rats were observed. Total protein contents were determined by Bradford method. The expression of c-fos protein was detected by Western blot. [Ca²⁺]i labeled with fluorescent probe Fluo-3/AM was measured under a laser scanning confocal microscope. The results revealed that as compared with control, the total protein contents were increased in cardiomyocytes treated with Ang II (10⁻⁷ mol/ L), which could be inhibited by CsA in a dose-dependent manner. It was found that Ang II could increase the c-fos protein expression, which could be inhibited by CsA in a dose-dependent manner. Ang II induced the [Ca²⁺]i elevation in cardiomyocytes. CsA did not influence the resting intracellular Ca²⁺, but inhibited significantly the Ang II-induced [Ca²⁺]i elevation. It was concluded that CsA can suppress the Ang II-induced c-fos protein expression and [Ca²⁺]i elevation in single cardiomyocyte, which might pay a role in the prevention of Ang II-induced cardiomyocyte hypertrophy by CsA. Han Zhaomin, female, born in 1974, Pharmacist     

大承气颗粒药物血清对小鼠肠上皮内淋巴细胞增殖的作用*

[目的]探讨大承气颗粒药物血清对小鼠肠上皮内淋巴细胞(IELs)的增殖作用及其作用途径.[方法]分离、鉴定、培养Balb/c小鼠IELs;制备不同浓度的大承气颗粒单次灌胃大鼠的药物血清和临床等效剂量的大承气颗粒多次灌胃大鼠的药物血清,并与大黄素、大黄酚等比较,观测其对IELs增殖及IELs[Ca2+]i的作用.[结果]IELs是CD3阳性细胞为(82.76±2.61),CD8阳性细胞为(72.48±3.57),CD4阳性细胞为(9.91±2.52)的淋巴细胞.单次灌胃的药物血清和多次灌胃的药物血清均能显著刺激IELs增殖.单次灌胃的药物血清对IELs的作用与大承气颗粒的浓度、采血时间、药物血清的作用时间等有关.稀释的药物血清比其原液及正常血清原液作用强.等摩尔浓度的大黄酚、大黄素、厚朴酚的作用以大黄酚较强.大鼠正常血清、药物血清和植物血凝素均能增加IELs[Ca2+]i.[结论]大承气颗粒药物血清能显著刺激IELs增殖,其作用途径之一是增加IELs[Ca2+]i,对维护肠免疫屏障有重要意义.     

双哌嗪类化合物的合成及钙通道阻滞活性

为寻求活性更好、毒性更低的新结构类型钙通道阻滞剂,以氟桂利嗪为先导化合物,设计合成了一系列双哌嗪类新化合物,并经光谱证明其结构。初步药理实验结果表明,9个新化合物在⁴⁵Ca²⁺跨膜内流动药理实验中,对大鼠主动脉电压依赖型钙离子通道（PDC）均有钙阻滞活性,且部分化合物的活性强于阳性对照药硝苯吡啶。     

Mechanism of anti-β-adrenoceptor antibody mediated myocardial damage in dilated cardiomyopathy

Summary Antibodies against β₁-adrenoceptor can be detected in serum of patients with dilated cardiomyopathy (DCM), which have β-agonist-like activity, and induce a positive chronotropic effect on cardiac myocytes by its persistence at full strength. Effects of the antibodies against β-adrenoceptor from sera of patients with DCM on myocardial cytotoxicity and cytoplasmic free Ca²⁺-concentration ([Ca²⁺]_i) were observed in the cultured single layer SD rat ventricular cells by using the cytotoxicity assay and fluorescent Ca²⁺- indicator fura-2/AM. The positive sera of the anti-β-adrenoceptor antibodies from patients with DCM markedly enhanced myocardial [Ca²⁺]_i. Betaloc, a β_i-receptor blocker, might inhibit the increase of the antibody-mediated myocardial [Ca²⁺]_i, and the sera from healthy donors had no effect on myocardial [Ca²⁺]_i. Our results suggest that the anti-β-adrenoceptor antibody might increase myocardial [Ca²⁺]_i and result in myocardial damage. The antibodies might activate receptor-gating [Ca²⁺]-channel, thereby causing myocardial [Ca²⁺]_i rise and calcium overload. Early use of betaloc is recommended in the treatment of dilated cardiomyopathy. This project was supported by the National Natural Science Fundation of China (No. 39370317).     

Effects of Xianzhen tablet on Na+ - K+ - ATPase and Ca2+ - Mg2+ - ATPase in erythrocytic membranes and viscosity of whole blood in non-insulin-dependent diabetes patients with Qi-Yin deficiency, Kidney deficiency and blood stasis

Objective: To assess the effects of Xianzhen tablet (XZT) on Na⁺-K⁺-ATPase and Ca²⁺-Mg²⁺-ATPase on erythrocytic membranes, viscosity of whole blood, plasma glucose and clinical manifestations.Methods: Seventy-two cases of non-insulin-dependent diabetes mellitus (NIDDM) patients with deficiency of both Qi and Yin, deficiency of the Kidney and blood stasis were selected, and the effects of treatment on Na⁺ K⁺ -ATPase, Ca²⁺-Mg²⁺-ATPase, whole blood viscosity, blood sugar and clinical symptoms were observed.Results: In XZT group (test group), activities of Na⁺ -K⁺ -ATPase and Ca²⁺ -Mg²⁺ -ATPase rose significantly (P < 0.01,P < 0.05) after treatment. Viscosity of whole blood and clinical manifestations also improved obviously. The total effective rate in lowering plasma glucose was 77.8% with fasting blood glucose (FBG) and 69. 4% with 2 hours postprandial plasma blood glucose (2°PBG). In the control group, viscosity of whole blood and clinical manifestations had no significant improvement. Its total effective rate in lowering plasma glucose was 41.7% with FBG and 38.9% with 2°PBG.Conclusions: XZT played a certain role in increasing activities of Na⁺ -K⁺ -ATPase and Ca²⁺ -Mg²⁺ -ATPase, decreasing viscosity of whole blood and plasma glucose and improving clinical manifestations. Therefore, XZT was experimentally manifested as an effective drug in treating NIDDM patients with Qi-Yin deficiency, renal deficiency and blood stasis.     

Effect of calmodulin and voltage-dependent Ca<Superscript>2+</Superscript> channel on the proliferation of heptoma cells induced by epidermal growth factor

Summary The effect of thyrosine kinase, calmodulin and voltage-dependent Ca²⁺ channel on the proliferation of hepatoma cells induced by EGF was studied. Hepatoma cell line SMMC7721 was cultured in RPMI1640 serum-free medium. DNA synthesis rate of hepatoma cells was measured by H-TdR incorporation. 10⁻⁹ mol/L EGF could significantly stimulate the proliferation of hepatoma cells (P<0.05), and this effect might be significantly inhibited by tyrosine kinase inhibitor (P<0.001). Calmodulin inhibitor W-7 had no effect on the basic phase of cultured hepatoma cells (P>0.05), but it had very significantly inhibitory effect on the proliferation of hepatoma cells induced by EGF (P<0.001). Voltage-dependent Ca²⁺ channel inhibitor Varapamil had no inhibition on the proliferation of hepatoma cells induced by EGF (P>0.05). It had no effect on the basic phase of cultured hepatoma cells, (P>0.05). It is suggested that tyrosine kinase and Ca²⁺-calmodulin-dependent pathway may play a critical role on the proliferation of heptoma cells induced by EGF and voltage-dependent Ca²⁺ channel is independent of the effect of EGF. WU Binwen, male, born in 1968, M. D., Ph.D.     

大鼠肺动脉平滑肌细胞膜钙激活氯通道与细胞质钙的关系及意义

目的观察大鼠肺动脉平滑肌细胞（PASMCs）膜钙激活氯通道（ClCa）与细胞质钙的关系及意义。方法大鼠PASMCs获取采用急性酶分离法。荧光光度法检测细胞质内游离钙离子浓度（[Ca^2＋]i）；全细胞膜片钳技术测定PASMCs钙激活氯电流（ICl（Ca））；等长张力测定法观察ClCa阻滞剂尼氟灭酸（NFA）和Indaryloxyacetic acid（IAA-94）对大鼠肺动脉张力的影响。结果环匹阿尼酸（CPA）和苯福林（PE）均可引起[Ca^2＋]i升高；升高的[Ca^2＋]i可以引出ICl（Ca）；NFA和IAA-94可以舒张CPA、PE引起的肺动脉环收缩。结论生理条件下大鼠PASMCs的ClCa是钙依赖性的；细胞外Ca^2＋内流及细胞质内Ca^2＋释放均可激活该通道，其参与了血管活性药诱导的肺动脉收缩。     

Effects of Total Flavonoids ofHippophae Rhamnoides L. on intracellular free calcium in cultured vascular smooth muscle cells of spontaneously hypertensive rats and Wistar-Kyoto rats

Objective: To explore the effects of total flavonoids ofHippophae rhamnoides L. (TFH), quercetin (Que) and isorhamnetin (Isor) on the intracellular free calcium ([Ca²⁺ ]_i) in vascular smooth muscle cells (VSMC) of spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY).Methods: Fluo 3-acetoxymethylester(Fluo-3/AM) was used to observe the effects of TFH (100mg/L) and its essential monomers, namely Que (l0^-4 mol/L) and Isor (l0^-4 mol/L) on changes of [Ca²⁺]_i in cultured SHR and WKY VSMC (abbr. to Ca-SHR & Ca-WKY) following exposure to high K⁺, norepinephrine (NE) and angiotensin II (Ang II), and to compare with the effects of verapamil (Ver).Results: (1) TFH, Que and Isor had inhibitory effects on resting Ca-SHR (P<0.05), but had no significant effects on Ca-WKY (P>0.05). (2) High K⁺ could increase Ca-SHR more significantly than Ca-WKY (P<0.05); TFH, Que and Isor could inhibit the elevation of [Ca²⁺]_i induced by high K⁺-depolarization, with the effects similar to that of Ver, and the effect on Ca-SHR was more significant than that on Ca-WKY (P<0.05). (3) NE and Ang II could increase Ca-SHR more significantly than Ca-WKY (P<0.05), TFH, Que and Isor had remarkably inhibitory effect on the elevation of Ca-SHR and Ca-WKY induced by NE or Ang II. (4) In the absence of extracellular Ca²⁺, TFH, Que and Isor also had certain inhibitory effect on Ca-SHR and Ca-WKY induced by NE, and the effect on the former was more significant than that on the latter(P<0. 05).Conclusion: TFH, Que and lsor might decrease the levels of [Ca²⁺]_i in VSMCs by blocking both voltage-dependent calcium channels (VDC) and receptor-operated calcium channels (ROC) in physiological or pathological state, which may be one of the important mechanisms of their hypotensive and protective effects on target organs in patients with hypertension. Supported by One-hundred-people Plan of Hygiene System in Shanghai (No. 990122)     

Effect of Huoxuequyu recipe on erythrocyte membrane Ca2+-ATPase activity in pregnant rats with asymmetrical intrauterine growth retardation induced by passive smoking

Summary The effect of Huoxuequyu recipe on erythrocyte membrane Ca²⁺-ATPase activity in pregnant rats with passive smoking induced asymmetrical intrauterine growth retardation (IUGR) was observed. The rats were divided into three groups: control group, model group and treated group. The fetal mean birth weight and erythrocyte membrane Ca²⁺-ATPase activity were found to be decreased in the model group as compared with the control and treated groups. There was a significant difference between the model group and the control group (P<0.01), while no significant difference existed between the treated group and the control group (P>0. 05). Furthermore, the findings indicated that the erythrocyte membrane Ca²⁺-ATPase activity seem to be positively correlated with the birth weight (P<0. 05). On the basis of our observation, it is believedthat the Huoxuequyu decoction could increase erythrocyte membrane Ca²⁺-ATPase activity and promote blood circulation, thereby exerting a beneficial effect on fetal development. This project is supported by the National Natural Sciences Foundation of China. No 39270826     

针刺对局灶性脑缺血大鼠海马神经元细胞[Ca2+]i的影响

[目的]研究脑缺血不同时点大鼠海马神经元内游离Ca²⁺浓度[Ca²⁺]_i及醒脑开窍针刺对其影响,探讨醒脑开窍针刺法早期干预对脑缺血的治疗作用。[方法]建立大脑中动脉所致局灶性脑缺血(MCAO)模型,采用醒脑开窍针刺法治疗,采用激光扫描共聚焦显微技术动态观察脑组织海马CA1区锥体细胞[Ca²⁺]_i在不同时间点的变化。[结果]与正常组大鼠相比,模型组大鼠脑组织海马CA1区锥体细胞内游离[Ca²⁺]_i(以细胞内Ca²⁺相对荧光强度表示)在局灶性脑缺血1 h时升高,持续升高至缺血24 h时(P<0.05)。假手术组与正常组相比[,Ca²⁺]_i变化差异无统计学意义(P>0.05)。相应时间点非穴位针刺组与模型组[Ca²⁺]_i比较,无统计学意义(P>0.05)。在相应时间点,醒脑开窍针刺组[Ca²⁺]_i低于模型组(P<0.01)。[结论]急性局灶性脑缺血后大鼠海马神经细胞[Ca²⁺]_i随缺血时间的延长而持续升高,提示细胞内钙超载;醒脑开窍针刺组能有效调节缺血区的[Ca²⁺]_i,提示在缺血后针刺治疗效果越早越好,为临床及早应用针刺治疗缺血性脑血管病提供了理论依据。     

胡颓子叶对豚鼠离体气管平滑肌收缩功能的影响

目的 研究胡颓子叶乙醇提取物正丁醇部位（胡颓子叶正丁醇部位）对正常及多种致痉剂诱导的豚鼠气管平滑肌收缩功能的影响。方法 制备豚鼠离体气管平滑肌螺旋条,在其正常状态下以及用乙酰胆碱、组胺、氯化钾、无钙下乙酰胆碱诱导细胞内钙释放和高钙下诱发细胞外钙内流条件下,观察胡颓子叶正丁醇部位对离体气管张力的影响。结果 胡颓子叶正丁醇部位对静息状态下的豚鼠离体气管平滑肌有明显的舒张作用,使乙酰胆碱和组胺的量效曲线发生明显右移,抑制加入高钾或高钙后引发细胞外钙内流导致的收缩。结论 胡颓子叶正丁醇部位能明显抑制正常状态及多种致痉剂诱发的豚鼠气管平滑肌收缩。     

旋覆代赭汤及其拆方对RE大鼠血浆Na+-K+-ATP酶及Ca2+-Mg2+-ATP酶活性的影响

[目的] 探讨反流性食管炎(RE)食管黏膜血浆细胞能量代谢与黏膜损伤的关系以及旋覆代赭汤治疗RE的作用机制。[方法] 将120只Wistar大鼠按照随机数字法随机分为10组,每组12只,即正常组、模型组、旋覆代赭汤全方组(全方组)、苦降组、甘升组、升降相因组、去苦降组、去甘升组、去升降相因组和西药组;除正常组外,其余9组行"4.2 mm幽门夹+胃底2/3结扎术"造模。治疗14 d后,即造模后第22天处死,检测各组大鼠血浆Na⁺-K⁺-ATP酶及Ca²⁺-Mg²⁺-ATP酶的活性。[结果] 实验后各模型组大鼠ATP酶活性低于正常组;全方组、西药组酶活性较好,与正常组差异无统计学意义(P>0.05),与模型组相比有统计学差异(P<0.05);苦降组及去甘升组与模型组相比,差异无统计学意义(P>0.05),与全方组及西药组比较差异有统计学意义(P<0.05);正常组与其他各组比较,均有统计学差异(P<0.05);西药组与全方组比较,差异无统计学意义。[结论] 旋覆代赭汤全方组能提高模型大鼠血浆Na⁺-K⁺-ATP酶及Ca²⁺-Mg²⁺-ATP酶的活性,改善模型大鼠食管黏膜组织形态学病变,且作用优于各拆方组。     

兰尼碱受体1结构及其通道门控机制的研究进展

兰尼碱受体(ryanodine receptor,RyR)是位于肌浆网膜上的细胞内Ca2+释放通道,在骨骼肌和心肌兴奋收缩偶联等生理过程中发挥重要作用.随着单粒子冷冻电镜技术的应用以及数据分析能力的提高,近期来自中国、美国以及德国的3个课题组分别获得了整体分辨率为3.8 (A)(1 (A)=10m)、4.8A和6.1A的高清晰RyR1结构图片,相关研究同时发表于2015年第1期的Nature上,是近年来RyR结构及其门控研究的重要进展.RyR1为相对分子质量＞2 200 000的同源四聚体离子通道,主要包括由NTD、SPRY、P1、P2、B-sol以及C-sol等结构域组成的胞质区和由SI～S6、VSL以及CTD等结构域组成的通道区.Ca2+作为RyR1门控的主要影响因子,能够与胞质区EF-hand亚结构域结合,引起通道构象的变化并最终导致通道的开放.