细胞保护新靶点——Na~+-Ca~(2+)交换体

Na+ Ca2 +交换体 (Sodium calciumexchanger,NCX)是一种双向转运蛋白 ,具生电特性 ,其产生的电流称为Na+ Ca2 +交换电流 (INa Ca)。Na+ Ca2 +交换是调节细胞内Ca2 +平衡的主要途径之一 ,更是将过多的Ca2 +排出细胞的主要方式。NCX活性受多种因素调节 ,且在心 (脑 )缺血 /再灌 ,心衰 ,早老性痴呆等病理状态下有不同程度的改变。NCX是一潜在的、重要的药物作用靶点 ,目前尚无特异性作用于NCX本身的药物     

简析钙拮抗剂在3类心血管疾病中的作用及应用

钙拮抗剂是一类主要作用于细胞膜表面慢通道,抑制Ca2+进入细胞而使细胞内Ca2+浓度下降的药物。而细胞内的Ca2+主要是使心肌的收缩力增强、自律性增高,血管平滑肌收缩,故钙拮抗剂可使心肌、血管平滑肌细胞的兴奋-收缩脱偶联,产生不同程度的负性肌力作用和血管扩张作用。钙拮抗剂的代表药物有:异搏定、硝苯地平、地尔硫卓等,尽     

药物血清对缺氧/复氧心肌细胞Ca~(2+)及NOS-NO系统的相关性研究

目的探讨双参通冠方药物血清对培养心肌细胞缺氧/复氧损伤的Ca2+超载、NOS-NO系统的影响。方法培养心肌细胞,建立缺氧/复氧损伤模型。运用血清药理学方法研究双参通冠方药物血清对缺氧/复氧心肌Ca2+超载、NOS-NO系统的影响。荧光分光光度法测定心肌细胞胞质[Ca2+]i,比色法检测心肌细胞培养上清NOS活性、NO含量。结果缺氧/复氧后[Ca2+]i增高,总NOS(T-NOS)及诱导型NOS(iNOS)活性增高,双参通冠方药物血清能降低缺氧/复氧心肌细胞[Ca2+]i,并能降低T-NOS、iNOS活性和NO含量(P<0.05)。结论双参通冠方药物血清可抑制缺氧/复氧损伤时心肌细胞Ca2+超载及NOS-NO系统的激活。     

小鼠精母细胞钙通道特性及硝苯地平的作用

目的　为了建立一个合理、客观评价药物或毒物对生殖系统影响的细胞模型 ,研究了机械分离、未经酶消化的小鼠精母细胞Ca2 + 通道特性及硝苯地平对其的作用。方法　采用全细胞膜片钳技术。结果阻断K+ 电流后 ,当钳制电位 -90mV、指令电压 -80～ +1 0mV、步阶电压 1 0mV时 ,记录到Ca2 +电流 ,二价无机阳离子对Ca2 + 电流的抑制作用Ni2 +>Cd2 + ,而L型Ca2 + 通道激动剂BayK8644对电流无任何影响。分析小鼠精母细胞上记录的Ca2 + 电流为T型Ca2 + 通道开放产生。L型Ca2 + 通道阻断剂硝苯地平对精母细胞Ca2 + 电流有明显的抑制作用 ,半数最大抑制浓度为 0 .3 9μmol·L-1,而且细胞外液冲洗恢复缓慢 ,这支持了二氢吡啶类药物可用于男性避孕。结论　机械分离、未经酶消化的小鼠精母细胞模型适合进行药理学和毒理学研究     

双参通冠方药物血清对缺氧/复氧心肌细胞Ca~(2+)-CaM-CaMPKⅡ信号系统的影响

目的考察双参通冠方(SSTG)药物血清对缺氧/复氧心肌细胞Ca2+-CaM-CaMPKⅡ信号系统的影响。方法培养心肌细胞,建立缺糖缺氧/复氧损伤模型。运用血清药理学方法研究SSTG药物血清对缺糖缺氧/复氧损伤心肌的作用。荧光分光光度法测定心肌细胞胞质[Ca2+]i,RT-PCR法测定CaM、CaMPKⅡδmRNA表达。结果正常心肌细胞[Ca2+]i、CaM、CaMPKⅡδmRNA表达很低。缺氧/复氧后[Ca2+]i较正常组增高,CaM、CaMPKⅡδmRNA表达增高(P<0.05),SSTG提取物大鼠灌胃剂量为22.5、45、90 mg.kg-1所取得的药物血清(体积分数为0.1)处理组[Ca2+]i降低,CaM、CaMPKⅡδmRNA表达降低,与空白血清处理组相比差异有统计学意义(P<0.05)。结论缺氧/复氧损伤可导致心肌细胞Ca2+超载,CaM、CaMPKⅡδmRNA表达增高;SSTG药物血清可对抗心肌细胞Ca2+超载,抑制其胞内受体CaM及Ca2+/CaM依赖性蛋白激酶CaMPKⅡδ的活性。     

谷氨酸触发大鼠大脑皮质神经元Ca~(2+)内流与PTK的关系

目的　研究谷氨酸 (glutamate,Glu)触发大鼠大脑皮质神经元Ca2 + 内流特性 ,蛋白酪氨酸激酶 (PTK)抑制剂genistein及蛋白酪氨酸磷酸酶 (PTP)抑制剂vanadate对其影响 ,揭示PTK与Glu触发大鼠大脑皮质神经元Ca2 + 内流的内在联系。方法　采用Fura 2 /AM荧光测定胞浆Ca2 + 变化技术 ,在原代培养的大鼠大脑皮质神经元上观察药物对Glu触发Ca2 + 内流的影响。结果　Glu触发的Ca2 + 内流不受电压依赖性钙通道 (VDCC)阻断剂尼莫地平影响 ,亦不受非VDCC阻断剂SK&F96 36 5影响 ,但可被PTK抑制剂genis tein抑制 ,被PTP抑制剂vanadate增强。genistein(1～ 30μmol·L-1)呈浓度依赖性抑制Glu触发的Ca2 + 内流。vana date则浓度依赖性增强Glu触发的Ca2 + 内流。结论　对尼莫地平敏感的VDCC及对SK&F96 36 5敏感的非VDCC没有参与Glu触发的Ca2 + 内流。PTK激活参与了Glu触发的Ca2 + 内流     

谷氨酸对牛大脑中动脉平滑肌细胞胞浆静息Ca2+和ATP触发的Ca2+内流的影响

目的观察谷氨酸对牛大脑中动脉平滑肌细胞有无直接的激动作用以及对ATP触发的Ca2+内流有无影响?方法采用Fura-2荧光法测定胞浆内Ca2+变化技术,在培养的乳牛大脑中动脉平滑肌细胞上观察药物的作用.结果谷氨酸(10～200μmol·L-1)不能增加或减少细胞胞浆静息游离Ca2+浓度([Ca2+]i)和ATP触发的Ca2+内流(谷氨酸10～400μmol·     

Cl~-通道阻断剂对5-HT和CPA引起的兔脑椎基底动脉平滑肌细胞Ca~(2+)内流的影响

目的　在培养的兔脑椎基底动脉平滑肌细胞上观察5 HT和CPA诱导的Ca2 + 内流的特性 ,电压依赖性Ca2 + 通道 (VDC)抑制药尼莫地平 ,非电压依赖性Ca2 + 通道抑制药SK&F963 65及Cl-通道阻断剂DIDS、NPPB对两种激动剂引起 [Ca2 + ]i 反应的影响 ,以探讨脑血管平滑肌细胞中 5 HT引起Ca2 + 内流的特性、Cl-通道与Ca2 + 内流的关系。方法　采用生物荧光双波长影像分析系统瞬即测定单细胞胞质[Ca2 + ]i 技术。结果　① 5 HT和CPA均能诱导平滑肌细胞[Ca2 + ]i 呈双相升高 ,并且 5 HT诱导的Ca2 + 释放是环匹阿尼酸 (CPA)敏感Ca2 + 池的一部分 ;②尼莫地平对 5 HT和CPA触发的Ca2 + 内流无明显影响 ,而SK&F963 65可阻止二者触发的Ca2 + 内流 ;③Cl-通道阻断剂DIDS、NPPB呈浓度依赖性抑制Ca2 + 内流 ,在SK&F963 65最大限度抑制Ca2 + 内流后 ,DIDS、NPPB可进一步抑制Ca2 + 内流 ;而Ca2 +内流被DIDS、NPPB分别最大抑制后 ,SK&F963 65也可进一步抑制Ca2 + 内流。结论　 5 HT引起的Ca2 + 内流是经SK&F963 65敏感的非VDC ,其中包含Ca2 + 释放引起的Ca2 + 内流 (CRAC)成分与非CRAC成分 ,并且这两部分Ca2 +内流均与DIDS、NPPB敏感的Cl-通道开放有关     

灯盏花素对人脐静脉内皮细胞胞内Ca~(2+)水平的调控作用

目的探讨灯盏花素对培养的人脐静脉内皮细胞(HUVECs)胞内Ca2+水平([Ca2+]i)的调控作用。方法采用新一代Ca2+荧光探针Fluo-3/AM标记培养的HUVECs,激光共聚焦显微镜检测细胞胞内钙荧光信号,观察灯盏花素对培养的HUVECs胞内Ca2+水平的调控作用。结果在胞外有Ca2+或无Ca2+的情况下,灯盏花素均可引起[Ca2+]i的短暂性升高;灯盏花素的Ca2+释放作用与钙泵抑制剂CPA存在着交迭;灯盏花素能够抑制由KCl所引起的[Ca2+]i的升高;灯盏花素对胞内Ca2+池耗竭后胞外复Ca2+所引起的钙内流无明显阻断作用。结论灯盏花素可引起胞内Ca2+池的Ca2+释放,其释放的Ca2+来自CPA敏感的Ca2+池。灯盏花素也可抑制经电压依赖性Ca2+通道的Ca2+内流,对Ca2+池耗竭后引起的Ca2+内流通道无明显阻断作用。     

丙泊酚对大鼠海马突触体释放谷氨酸和γ-氨基丁酸的影响

目的观察丙泊酚对大鼠海马突触体谷氨酸和γ氨基丁酸(GABA)Ca2+依赖性释放和非Ca2+依赖性释放的影响。方法制备突触体后用人工脑脊液(aCSF)孵育,分为7组,应用丙泊酚(propofol)的浓度分别为3(Pro3组)、10(Pro10组)、30(Pro30组)、100(Pro100组)和300μmol·L-1(Pro300组),脂肪乳剂对照组加入脂肪乳(Intralipid组),空白对照组(Control组)不加入任何药物。在观察Ca2+依赖性释放时,加入二氢海人藻酸和哌啶酸;在观察非Ca2+依赖性释放的时候,去除aCSF中的Ca2+。在37℃的条件下,应用20μmol·L-1藜芦定或30mmol·L-1KCl诱发递质释放。应用反相高效液相色谱法测定aCSF中谷氨酸和GABA的浓度。结果①Ca2+依赖性递质释放:应用藜芦定时,Pro30、Pro100和Pro300组的谷氨酸和GABA释放量低于Intralipid组(P<0.01或P<0.05);应用KCl时,各组的谷氨酸和GABA释放量无差异(P>0.05)。②非Ca2+依赖性释放:各组应用藜芦定和KCl诱发的谷氨酸和GABA释放量无差异(P>0.05)。结论丙泊酚可以抑制Ca2+依赖性谷氨酸和GABA的释放,而对非Ca2+依赖性谷氨酸和GABA释放无影响。     

Effects of resveratrol on calcium regulation in rats with severe acute pancreatitis

Intracellular calcium overload plays a key role in severe acute pancreatitis. Resveratrol can decrease the severity of pancreatitis; however, the mechanism of action of resveratrol has not been determined. The aim of our study was to examine the relationship between calcium overload and the effects of resveratrol in severe acute pancreatitis. Animals were randomly divided into 3 groups: control group (sham operation), model group (0.1 ml/100 g of 3.5% sodium taurocholate used to induce severe acute pancreatitis), and treated group (treated with resveratrol, 10 mg/kg). In model group, the severity of pancreatitis was aggravated; this was evaluated by pancreatic weight/body weight and lung weight/body weight ratios, serum amylase activities, and pancreatic histopathological scoring; the Ca(2+)-Mg(2+)-ATPase and Ca(2+)-ATPase activities decreased while PLA(2) activity and [Ca(2+)](i) increased gradually with time. Compared to the control group, in the model group, these changes were observed in the pancreatic tissue at the 3 h time point and in the lung tissue at the 6 h time point. Resveratrol ameliorated the changes in the laboratory parameters and significantly reduced the pathological damage in the tissues at the corresponding time points. In conclusion, intracellular calcium overload leads to tissue damage in severe acute pancreatitis, and the beneficial effects of resveratrol appear to be mediated by reducing the intracellular calcium overload; this not only limits pancreatic cellular injury but also secondary lung injury.     

银杏苦内酯对急性胰腺炎大鼠的治疗作用及机制

观察血小板活化因子受体特异性拮抗刘银杏苦内酯（ＢＮ５２０２１）对牛磺胆酸钠诱导的急性胰腺炎（ＡＰ）大鼠的治疗作用及其对胰腺组织丙二醛（ＭＤＡ）．ＳＯＤ和Ｃａ２＋的影响。结果表明：ＢＮ５２０２１显著降低ＡＰ大鼠死亡率，延长平均存活时间、降低血清淀粉酶活性、减轻胰组织病理损伤；显著降低胰组织Ｃａ２＋含量和ＭＤＡ含量、提高ＳＯＤ活性。提示ＢＮ５２０２１对ＡＰ大鼠有一定治疗作用，此与其抑制钙超载、清除自由基有关。     

Ca2+ signalling and pancreatitis: effects of alcohol, bile and coffee

Ca2+ is a universal intracellular messenger that controls a wide range of cellular processes. In pancreatic acinar cells, acetylcholine and cholecystokinin regulate secretion via generation of repetitive local cytosolic Ca2+ signals in the apical pole. Bile acids and non-oxidative alcohol metabolites can elicit abnormal cytosolic Ca2+ signals that are global and sustained and result in necrosis. Necrosis results from excessive loss of Ca2+ from the endoplasmic reticulum, which is mediated by Ca2+ release through specific channels and inhibition of Ca2+ pumps in intracellular stores, followed by entry of extracellular Ca2+. Reduction of the cellular ATP level has a major role in this process. These abnormal Ca2+ signals, which can be inhibited by caffeine, explain how excessive alcohol intake and biliary disease cause acute pancreatitis, an often-fatal human disease in which the pancreas digests itself and its surroundings.     

高脂血症性急性胰腺炎的临床特点及相关分析

目的了解高脂血症性急性胰腺炎（HL—AP）的临床特点,提高对HL-AP的认识。方法回顾159例急性胰腺炎（AP）患者资料,其中18例HL-AP、141例为其他病因的AP,对两组的年龄、甘油三酯（TG）、血钙（Ca^2＋）、血糖（GLU）、CT严重指数（CTSI）、急性生理和慢性健康评分（APACHEII）及合并糖尿病酮症酸中毒（DKA）的发生率进行比较,并将HL-AP组的TG值与上述指标进行相关分析。结果HL-AP组与对照组相比除Ca^2＋明显下降外,TG、APACHEⅡ评分、CTSI、GLU和合并DKA的发生率均显著性增高（均P〈0．05）。HL-AP组TG值和APACHEⅡ评分、CTSI均呈正相关（均P〈0．05）;TG值和Ca^2＋水平存在直线负相关（r=-0．795,P〈0．01）关系。结论HL-AP临床并不少见,其血清TG水平与HL-AP的病变程度呈正相关,且病情较严重,应重视对HL-AP的早期诊断和治疗。     

依他尼酸抑制胰腺外分泌

AIM: The effect of ethacrynic acid on pancreaticexocrine secretion function and potential mechanisms ofinterference with the secreory process in pancreatic acinarcells were investigated. METHODS: After incubationwith ethacrynic acid for 30 min, caerulein-stimulatedamylase release and cholecystokinin (CCK) receptorbinding characteristics were assessed in isolated ratpancreatic acini. The level of thiol groups (glutathioneand protein thiols) and cytosolic free calcium weremeasured in pancreatic acinar cells. RESULTS:Ethacynic acid decreased caerulein (0. 1 nmol/L)-stimulated amylase release and the level of pancreaticacinar glutathione in a concentration-dependent fashionwithout a marked increase in cell damage. Ethacrynicacid also inhibited the caerulein (1 nmol/L)-inducedCa~(2 ) mobilization in pancreatic acinar cells. But neitherprotein thiol nor CCK-receptor binding characteristics wasaltered by ethacrynic acid. CONCLUSION: Ethacrynicacid inhibit pancreatic exocrine secretion by depletion ofglutathion     

Protective effect of the combined treatment of pancreatic and neutrophil elastase inhibitors on acute pancreatitis elicited by lipopolysaccharide in rats given intraductal injection of taurocholate plus trypsin

A severe acute pancreatitis was produced by intraperitoneal injection of lipopolysaccharide (LPS) in rats with preexisting hemorrhagic and necrotizing pancreatitis induced by retrograde injection of a 5% taurocholate plus 1% trypsin solution into the pancreatic duct. Mortality and time-course changes in pancreatic, hepatic, renal and pulmonary functions, and organ myeloperoxidase (MPO) levels were examined in this model. LPS at an intraperitoneal dose of 30 mg/kg, which scarcely caused death and had no marked effect on serum parameters and organ MPO levels in rats without pancreatitis, increased the mortality in rats with taurocholate plus trypsin-induced pancreatitis. Pancreatic weight and ascitic volume increased in rats with taurocholate plus trypsin-induced pancreatitis regardless of the presence or absence of LPS. Serum amylase and lipase levels were also significantly increased in rats with induced pancreatitis, but was higher in the group given LPS. Serum glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), blood urea nitrogen (BUN) and creatinine levels were significantly elevated in LPS-treated rats with induced pancreatitis, whereas levels in rats with induced pancreatitis not given LPS were only slightly elevated. Renal weight was also significantly increased in rats with induced pancreatitis despite the presence or absence of LPS. In LPS-treated rats with induced pancreatitis, the arterial oxygen pressure, pulmonary weight and pulmonary MPO level were significantly elevated. However, the MPO level in the kidney in these rats was not different from that in control rats, indicating that the renal dysfunction was not produced by the infiltration of neutrophils into the kidney. Increase in the pancreatic MPO level was observed in rats with induced pancreatitis, but combination treatment with LPS did not raise it. Protective effects of prophylactic treatment of 2-(3-methylsulfonylamino-2-oxo-6-phenyl-1,2-dihydro-1-pyridyl)-N-(3,3,3-trifluoro-1-isopropyl-2-oxopropyl)acetamide (compound 1), a neutrophil elastase inhibitor, and trifluoroacetyl-L-lysyl-L-alaninanilide hydrochloride (compound 2), a pancreatic elastase inhibitor, on mortality were also examined in this model. Results were compared with that of the combined treatment of compound 1 and compound 2. In LPS-treated rats with taurocholate plus trypsin-induced pancreatitis, the combined treatment of compound 1 (2 mg/kg/h) and compound 2 (30 mg/kg/h) significantly reduced mortality, whereas single treatment of compound 1 or compound 2 did not show the beneficial effect. These results suggest that marked hepatic and renal dysfunction accompanies pancreatitis in this pancreatitis model rats, which may be good models for acute pancreatitis in humans. It is also suggested that neutrophil and pancreatic elastases may be synergistically involved in the pathogenesis of acute pancreatitis in this model. Received: 24 November 1997 / Accepted: 10 February 1998     

急性胰腺炎细胞免疫功能、血清中细胞因子的测定及临床意义

目的:观察急性胰腺炎病人细胞免疫功能、血清中细胞因子的变化,探讨他们在急性胰腺炎发病机理中的作用。方法:采用流式细胞仪,测定急性胰腺炎病人T淋巴细胞亚群,采用酶联免疫吸附实验测定急性胰腺炎病人血清中IL-2、IL-8。结果:T淋巴细胞亚群中CD4阳性细胞百分比和CD4/CD8比值在急性胰腺炎病人中降低,IL-2、在惠性胰腺炎病人中降低、IL -8在急性胰腺炎病人中增高。结论:急性胰腺炎症过程中存在细胞免疫功能低下,且有多种细胞因子参与其发病机理,某些细胞因子的升高与疾病的严重程度相关。     

重症急性胰腺炎患者早期胰腺感染的危险因素分析

目的 分析重症急性胰腺炎(severe acute pancreatitis,SAP)患者早期胰腺感染的危险因素,为SAP早期胰腺感染防治提供依据.方法 选择2012年8月至2014年12月在我院收治的96例SAP患者的病历资料进行回顾性分析,其中合并胰腺感染45例作为观察组,未合并感染51例作为对照组.对两组患者的年龄、性别、就诊时间、APACHEⅡ评分、血淀粉酶(Amylase,AMS)、血钙(Ca2+)、糖尿病史、低氧血症、机械通气进行单因素变量分析,并将具有统计学差异的单因素进行Logistic多因素分析.结果 单因素分析显示,两组APACHEⅡ评分、AMS、Ca2+、糖尿病史、低氧血症、机械通气的差异有统计学意义(t/x2=7.118,3.590,8.149,3.697,3.079,1.391;P＜0.05),即上述指标为SAP患者早期胰腺感染发生的危险因素;多因素回归分析显示,APACHEⅡ评分、糖尿病史、低氧血症是SAP患者早期胰腺感染发生的独立危险因素.结论 SAP患者早期胰腺感染的发生与APACHE Ⅱ评分、糖尿病史、低氧血症等密切相关,医师应密切关注上述危险因素,进而避免或降低早期胰腺感染的发生.     

Pharmacological studies of 6-amidino-2-naphthyl 4-[(4,5-dihydro-1H-imidazol-2-yl)amino]benzoate dimethanesulfonate. Effects on experimental pancreatitis

The effects of FUT-187 (6-amidino-2-naphthyl 4-[(4,5-dihydro-1H-imidazol-2-yl)amino]benzoate dimethanesulfonate, CAS 103926-82-5), a novel synthetic protease inhibitor, were examined in experimental rat and canine models of pancreatitis. 1. FUT-187 significantly increased the survival of rats with trypsin- and phospholipase A2-induced pancreatitis in a dose-dependent manner (10-100 mg/kg, p.o.). 2. FUT-187 decreased plasma enzymatic activity reflecting the degree of pancreatitis in rats with ethionine-induced pancreatitis, and showed a tendency to ameliorate histopathological changes in the pancreas (10-100 mg/kg p.o.). 3. FUT-187 (10 mg/kg) produced an obvious improvement of various biochemical parameters of pancreatitis and also reduced histopathological changes in the pancreas in animals with experimental pancreatitis produced by the closed duodenal loop method. In addition, FUT-187 significantly increased the survival of dogs when given by direct administration into the lumen of the closed duodenal loop. The therapeutic effects of FUT-187 in experimental pancreatitis were nearly equal in most instances to those of camostat mesilate. Thus, FUT-187 would appear to be an effective new agent for the treatment of pancreatitis.     

急性胰腺炎120例治疗分析

目的探讨不同类型及不同阶段的急性胰腺炎(AP)的治疗选择。方法总结2000年1月~2004年12月的120例急性胰腺炎治疗的临床资料。结果120例急性胰腺炎中,急性轻症胰腺炎(MAP)85例全部治愈,急性重症胰腺炎(SAP)35例,其中2例死亡,并发胰周脓肿2例,胰腺假性囊肿2例,肠瘘1例,其余均治愈。结论对AP伴腹腔积液或弥漫性腹膜炎应予腹腔穿刺灌洗引流、胃管内注或外敷中药等保守治疗,MAP很快治愈;胆道梗阻立即手术或行鼻胆管引流保守治疗,延期手术以消除再发病因。如胰腺感染,立即手术。