丹皮酚对体外培养乳鼠心肌细胞~(45)Ca摄取的影响

通过测定体外培养乳鼠心肌细胞~(45)Ca摄取及其搏动频率的变化,观察丹皮酚对心肌细胞Ca~(2+)内流的影响。结果50～400μg/ml的丹皮酚,能显著降低心肌细胞搏动频率,对心肌细胞快相(5min)和慢相(120min)~(45)Ca摄取均有显著抑制作用,且400μg/ml丹皮酚与10μmol/L的维拉帕米的作用相似。提示丹皮酚能抑制心肌细胞的Ca~(2+)内流,可能与阻滞慢钙通道有关。     

异丙酚和硫喷妥钠对心肌细胞毒性作用的对比研究

目的 对比研究异丙酚和硫喷妥钠对心肌细胞的毒性作用.方法 将经原代培养成活4d后的大鼠心肌细胞分为5组,分别为对照组、小剂量异丙酚组(PL,3×10~(-5) mol·L~(-1))、大剂量异丙酚组(PH,3×10~(-4)mol·L~(-1))、小剂量硫喷妥钠组(TL,1×10~(-5) mol·L~(-1))和大剂量硫喷妥钠组(TH,1×10~(-4)mol·L~(-1)).各组均于实验开始后8h终止反应,评定心肌细胞搏动功能、观察细胞形态学改变、测定心肌细胞酶及电解质变化.结果 与对照组相比,PH及TL组搏动频率明显减慢(P<0.05和P<0.01),TH组可见心肌细胞呈部分搏动或无搏动,三组细胞形态学亦有相应变化;LDH、AST与CK释放量增加(P<0.05和P<0.01),ALP活性下降.而PL组的上述指标无明显变化.各组间电解质变化未见显著差异.结论 低浓度的硫喷妥钠及高浓度的异丙酚均有直接的心肌抑制作用,高浓度的硫喷妥钠尤为明显.而低浓度异丙酚未见心肌细咆毒性作用.     

羟丁酸钠和氯胺酮对心肌细胞毒性作用的对比研究

目的对比研究羟丁酸钠和氯胺酮对原代培养大鼠心肌细胞的毒性作用。方法将经原代培养成活4d后的大鼠心肌细胞分为5组 ,每组6孔。包括对照组 ,小剂量(HL ,3×10-3mol·L -1)与大剂量(HH ,3×10 -2mol·L -1)羟丁酸钠组和小剂量(KL ,1×10 -5mol·L -1)与大剂量(KH ,1×10-4 mol·L-1)氯胺酮组。各组均于实验开始后8h终止反应 ,评定心肌细胞搏动功能、观察细胞形态学改变、测定心肌细胞酶及电解质变化。结果与对照组相比 ,KL组心肌细胞搏动频率明显加快(P<0.05) ,而KH组减慢(P<0.05)。细胞形态学亦有相应变化。KH组LDH和AST释放量增加(P<0.05) ,ALP活性下降(P<0.05)。而HL、HH组的上述指标均无明显变化。各组间电解质变化未见显著差异。结论高浓度的氯胺酮具有直接的心肌抑制作用 ,而低浓度的氯胺酮却有正性变时性和变力性作用。无论低浓度或高浓度的羟丁酸钠 ,均未见心肌细胞毒性作用。     

八肽胆囊收缩素对抗吗啡抑制大鼠脑突触小体钙摄取的作用

用大鼠脑的膜制备观察吗啡和CCK-8对突触小体摄取~(45)Ca~(2+)的影响。吗啡(10 nmol/L～1μmo1/L)抑制突触小体对~(45)Ca的摄取,该作用能被1μmol/L纳洛酮完全阻断。CCK-8(10nmol/L～1μmol/L)本身能抑制突触小体~(45)Ca摄取,但它在10nmol/L和100 nmol/L时能对抗吗啡对~(45)Ca摄取的抑制作用,浓度提高到1μmol则不能对抗吗啡的这一作用。CCK-8抑制突触小体摄取~(45)Ca,以及对抗吗啡的~(45)Ca摄取抑制的作用,皆能被CCK受体拮抗剂丙谷酰胺(2μmol/L)所阻断.捉示CCK-8是通过激动CCK受体而拮抗吗啡抑制~(45)Ca摄取的,CCK-8的这一拮抗作用可能是其抗阿片作用的机理之一.     

雷公藤甲素对新生大鼠心肌细胞搏动的影响

目的 探讨雷公藤甲素对新生大鼠心肌细胞搏动的影响.方法 新生大鼠心肌细胞予0、2.5、5、10、20、40、80、160和200 μmol/雷公藤甲素处理,采用实时细胞分析系统(RTCA)于给药前至给药后20 h连续记录心肌细胞搏动频率的变化.结果 浓度大于等于2.5 μmol/L的雷公藤甲素于给药后10 min可明显...     

氯胺酮对培养大鼠乳鼠缺氧心肌细胞的影响

目的探讨氯胺酮对原代培养心肌细胞缺氧损伤的影响。方法将原代培养成活48h的大鼠乳鼠心肌细胞分为3组:对照组(氰化钠造成心肌细胞细胞内缺氧模型),氯胺酮1组(缺氧+10μmol/L氯胺酮),氯胺酮2组(缺氧+100μmol/L氯胺酮)。比较3组心肌细胞形态学的变化及吸光度(A)值的改变。结果缺氧12h后,对照组细胞搏动功能变化明显,呈散在细胞簇状搏动,而实验组搏动频率减慢。随着时间的延长,细胞形态学变化逐渐明显,对照组较实验组变化更显著。结论氯胺酮对原代培养大鼠乳鼠心肌细胞缺氧损伤有一定的保护作用。     

乳鼠心肌细胞的原代培养方法改良

目的探讨乳鼠原代心肌细胞分离、培养和纯化的方法,得到存活率高、搏动频率强、纯度高的心肌细胞。方法采用0.08%胰蛋白酶及0.05%Ⅱ型胶原酶消化心脏组织,差速贴壁60 min,加入终浓度为0.1 mmol·L~(-1)的5-Brdu纯化心肌细胞。倒置显微镜下观察不同时间心肌细胞形态学变化;记录心肌细胞搏动频率;台盼蓝染色,测定心肌细胞存活率。结果心肌细胞生长状态良好,4 h开始贴壁,48~72 h基本完全贴壁,形成放射状排列的细胞簇,同步搏动;5~9 d心肌细胞搏动频率在80~110次·min~(-1),活力好且稳定;采用台盼蓝染色法测得心肌细胞平均存活率为97.7%。结论此方法可得到存活率高、搏动频率强、纯度较高的心肌细胞,可为科研研究提供良好的实验模型。     

咳喘宁合剂中氨茶碱和吗啡含量测定方法的建立

目的建立咳喘宁合剂中氨茶碱和吗啡含量测定的HPLC方法。方法采用高效液相色谱法,色谱柱为资生堂C8色谱柱,流动相为0.1 mol/L磷酸二氢钾溶液-0.005 mol/L庚烷磺酸钠水溶液-乙腈(47.5∶47.5∶5)。氨茶碱检测波长为271 nm,进样量为10μL;吗啡检测波长为207 nm,进样量为20μL。结果茶碱在8.62~68.96μg/m L范围内具有良好的线性关系,平均回收率为99.2%;吗啡在1.03~51.60μg/m L范围内具有良好的线性关系,平均回收率为101.5%。结论该方法具有良好的准确度、精密度、专属性,能良好地控制咳喘宁合剂的质量。     

δ阿片受体激活对培养心肌细胞生长的影响

目的观测δ阿片受体激活对培养的心肌细胞是否有直接的促生长作用。方法体外培养乳大鼠心肌细胞。结晶紫法和[3H]TdR法测定心肌细胞的增生;流式细胞仪测定细胞周期百分比;Lowry等法测定培养细胞蛋白质含量;倒置显微镜下计数心肌细胞搏动频率。结果δ阿片受体激动剂D-丙(2)-D-亮(5)脑啡肽(DADLE)10 nmol.L-1~10μmol.L-1能浓度依赖性促进细胞增殖,增加细胞蛋白质含量,增加细胞搏动频率;高选择性δ阿片受体拮抗剂纳曲吲哚(naltrindole)10μmol.L-1对DADLE的促进作用有一定的抑制作用。结论δ阿片受体激活对体外培养的心肌细胞生长有促进作用。     

山莨菪碱对乙酰胆碱和去甲肾上腺素引起的兔虹膜释放前列腺素的影响

本文研究了654-2对Ach及NE引起的兔虹膜释放PGE_2及6-keto-PGF_(1α)作用的影响。Ach及NE使虹膜释放PGs增加,654-2对Ach释放PGs的作用呈剂量依赖性抑制,当654-2浓度为3×10~(-5)mol/L时,Ach(5x10~(-5)mol/L)引起的PGE_2及6-keto-PGF_(1α)的释放量分别降低31%及30%。654-2浓度高于6x10~(-5)mol/L时显著抑制NE(5x10~(-5)mol/L)释放虹膜PGs的作用,当654-2浓度为3x10~(-4)mol/L时,使NE增加虹膜释放PGE:及6-keto-PGF_(1α)的量分别从62%及34%降至7.5%及4%(p<0.01)。654-2抑制PGs释放对其抗感染性休克等作用可能是有利的。     

吗啡对体外培养的人正常输卵管黏膜上皮细胞内MOR mRNA表达的影响

目的:研究吗啡对体外培养的人输卵管粘膜上皮细胞的μ阿片受体信使核糖核酸(MOR mRNA)表达的影响。方法:体外分离培养人输卵管粘膜上皮细胞,并通过免疫细胞化学的方法进行鉴定;将细胞分为对照组、吗啡组(10-4、10-5、10-6、10-7mol.L-1),通过RT-PCR的方法半定量分析吗啡对人输卵管粘膜上皮细胞MOR mRNA表达的影响。结果:吗啡组人输卵管粘膜上皮细胞中的MOR mRNA表达较对照组显著下降(P<0.05),且与吗啡浓度负相关(r=-0.966,P<0.05)。结论:外源性阿片类药物吗啡抑制人输卵管粘膜上皮细胞μ阿片受体mRNA的表达。     

ANTIDIURETIC EFFECTS OF NEUROTENSIN IN CHLORALOSE ANAESTHETIZED DOGS

1. Effects of cerebroventricular and/or intravenous infusions of neurotensin (NT), an endogenous tridecapeptide, on haemodynamics and renal function were investigated in chloralose anaesthetized dogs. 2. Cerebroventricular infusions (i.c.v.) of NT (10-6 mol/L and 10-5 mol/L, 0.1 mL/min) for 30 min did not produce any significant alterations in the measured variables. In the vagotomized dogs, intravenous (i.v.) infusion of NT (10(-5) mol/L) at a rate of 0.1 mL/min for 30 min significantly lowered the arterial blood pressure and glomerular filtration rate; these effects were accompanied by pronounced reductions in the urine flow and urinary sodium excretion and marked increases in urine osmolality. 3. In the dogs with vagi intact, i.v. infusions of NT failed to produce any alterations in the blood pressure; however, renal effects of NT were essentially identical to those observed in the vagotomized dogs. 4. Infusions of NT (10(-6) mol/L) and/or NT-metabolites NT1-8 and NT8-13 (10(-5) mol/L) directly into the renal artery failed to produce any significant alterations in the urine flow. Antidiuretic effects of i.v. NT were not prevented by acute renal denervation, adrenalectomy, or pretreatment of the animals with naloxone. However, morphine pretreatment completely abolished the hypotensive and anti-diuretic effects of NT. 5. It is proposed that i.v. infusion of NT rapidly facilitates the secretion of an endogenous substance possessing potent antidiuretic properties and opiate mechanisms are involved in mediating such an effect. Although it appears unlikely, a role for vasopressin cannot be ruled out.     

Differential modulation of bradykinin-induced relaxation of endothelin-1 and phenylephrine contractions of rat aorta by antioxidants

AIM: We tested the hypothesis that bradykinin (BK)-induced relaxation of phenylephrine (PE) and endothelin-1 (ET-1) contractions can be differentially modulated by reactive oxygen species (ROS). METHODS: Aortic rings isolated from Sprague-Dawley rats were used for the study. The contribution of ROS to PE (1 x 10(-9)-1 x 10(-5) mol/L)- and ET-1 (1 x 10(-10)-1 x 10(-8) mol/L)-induced contractions and the influence of ROS in BK (1 x 10(-9)-1 x 10(-5) mol/L) relaxation of PE (1 x 10(-7) mol/L) or ET-1 (1 x 10(-9) mol/L)-induced tension was evaluated in the aorta in the presence or absence of the following antioxidants: catalase (CAT, 300 U/mL), superoxide dismutase (SOD, 300 U/mL), and vitamin C (1 x 10(-4) mol/L). Results: Tension generated by ET-1 (1 x 10(-9) mol/L) or PE (1 x 10(-7) mol/L) was differentially relaxed by BK (1 x 10(-5) mol/L), producing a maximal relaxation of 75%+/-5% and 35+/-4%, respectively. The BK (1 x 10(-5) mol/L)-induced relaxation of PE (1 x 10(-7) mol/L) tension was significantly enhanced from 35%+/-4% (control) to 56%+/-9%, 60%+/-5%, and 49%+/-6% by SOD, CAT, and vitamin C, respectively (P<0.05, n=8). However, the relaxation of ET-1 (1 x 10(-9) mol/L) tension was significantly attenuated from 75%+/-5% (control) to 37%+/-9%, 63%+/-4%, and 39%+/-7% by SOD, CAT, and vitamin C, respectively (P<0.05, n=8). On the other hand, CAT had no effect on PE-induced tension, while SOD enhanced PE-induced tension (36%, P<0.05, n=10) and vitamin C attenuated (66%, P<0.05, n=8) the tension induced by PE. By contrast, SOD or vitamin C had no effect, but CAT attenuated (44%, P<0.05, n=9) the tension induced by ET-1. CONCLUSION: We have demonstrated that O2(-) and H2O2 differentially modulate BK relaxation in an agonist-specific manner. O2(-) attenuates BK-induced relaxation of PE contraction, but contributes to the relaxation of ET-1 contraction. O2(-) seems to inhibit PE contraction, while H2O2 contributes to ET-1-induced contraction. Thus, ROS differentially modulate vascular tone depending on the vasoactive agent that is used to generate the tone.     

纳洛酮改变慢性吗啡处理大鼠血管反应性和培养的血管细胞内信号转导

目的:探讨吗啡戒断反应对血管反应性及其细胞内信号转导的影响。方法:大鼠注射递增剂量的吗啡两周后iv纳洛酮催瘾,记录乙酰胆碱(Ach)的降压效应。用含不同药物的Kreb’s液灌流大鼠离体肠系膜血管床。AR-CM-MIC阳离子测定系统检测培养牛胸主动脉内皮细胞(aec)和血管平滑肌细胞(smc)胞浆内游离钙([Ca~(2 )]_i)。计算smc呈磷酸化cAMP反应元件结合蛋白(Phospho-CREB)免疫阳性反应的比例。结果:纳洛酮iv 2mg/kg催瘾后钝化的Ach降压效应同催瘾前一致。以纳洛酮25μmol/L取代灌流液所含吗啡20μmol/L使成瘾大鼠肠系膜血管的去甲肾上腺素(NE)升压效应的EC_(50)(μmol/L)从2.06±0.38降至1.14±0.21(n=8,P<0.01),而吗啡40μmol/L完全预防NE的作用。即时加入吗啡后对照组血管平滑肌细胞内[Ca~(2 )]_i反应不一。纳洛酮使2/3的吗啡预处理组的血管平滑肌细胞内[Ca~(2 )]_i显著升高,呈Phospho-CREB免疫阳性反应的比例也因之增加。部分内皮细胞的[Ca~(2 )]_i明显下降。结论:纳洛酮增加慢性吗啡处理大鼠血管的反应性可能与血管平滑肌细胞内钙增加有关,并伴有cAMP反应元件结合蛋白的磷酸化增强。     

肾上腺髓质素对CAOV3细胞增殖的影响

目的观察肾上腺髓质素（adrenomedullin,AM）对体外培养的人上皮性浆液性卵巢癌细胞株（CAOV3细胞）增殖的影响。方法将CAOV3细胞进行体外培养,以不同浓度的AM（1-52）（1×10-9mol/L、1×10-8mol/L、1×10-7mol/L、1×10-6mol/L）分别处理CAOV3细胞24h,四甲基偶氮唑蓝（MTT）比色法测定细胞的增殖率。结果在AM（1-52）浓度为1×10-9mol/L、1×10-8mol/L、1×10-7mol/L、1×10-6mol/L时均可促进CAOV3细胞增殖（P〈0.05）,随着AM（1-52）浓度的增高细胞的增殖率逐渐增高。结论AM能显著促进CAOV3细胞的增殖。     

Differential regulation of RGS proteins in the prefrontal cortex of short- and long-term human opiate abusers

Opiate addiction is characterized by drug tolerance and dependence which involve adaptive changes in μ-opioid receptors (MORs) signaling. Regulators of G-protein signaling RGS9, RGS4 and RGS10 proteins negatively regulate G(αi/o) protein activity modulating MOR function. An important role of RGS proteins in drug addiction has been described but the status of RGS proteins in human brain of opiate addicts remains unknown. The present study evaluated the immunoreactivity levels of RGS4, RGS9 and RGS10 proteins in prefrontal cortex of short- (n = 15) and long-term (n = 21) opiate abusers and in matched control subjects. RGS4 protein was not altered in short-term opiate abusers but, in long-term abusers it was significantly up-regulated (Δ = 29 ± 6%). RGS10 protein expression was significantly decreased in short-term (Δ = -42 ± 7%) but remained unaltered in long-term opiate abusers. RGS9 protein levels in opiate abusers did not differ from matched controls either in the short-term or in the long-term opiate abuser groups. RGS4, RGS9 and RGS10 levels were also studied in brains (frontal cortex) of rats submitted to acute and chronic morphine treatment and to spontaneous and naloxone-precipitated opiate withdrawal. Chronic morphine treatment in rats was associated with an increase in RGS4 protein immunoreactivity (Δ = 28 ± 7%), which persisted in spontaneous (Δ = 35 ± 8%) and naloxone-precipitated withdrawal (Δ = 30 ± 9%) without significant changes in RGS9 and RGS10 proteins. The specific modulation of RGS4 and RGS10 protein expression observed in the prefrontal cortex of opiate abusers might be relevant in the neurobiology of opiate tolerance, dependence and withdrawal. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.     

Influence of vasoactive intestinal polypeptide on net water flux and cyclic adenosine 3′,5′-monophosphate formation in the rat jejunum

1. The effects were studied of vasoactive intestinal polypeptide (VIP), theophylline, and morphine on net water flux and cyclic adenosine 3',5'-monophosphate (cyclic AMP) levels in the jejunum of anaesthetized rats in vivo and of VIP and morphine on adenylate cyclase activity in rat epithelial cell membranes in vitro. 2. Infusion of VIP (0.1-2 x 10(-9) mol/min/kg) dose dependently caused a reversal from net water absorption to net secretion; 2 x 10(-9) mol/min/kg enhanced the mucosal cyclic AMP content by 67%. 3. Theophylline (5 mg/ml, intraluminally) enhanced the effect of intra-arterial infusion of VIP (2 x 10(-9) mol/min/kg) as to net water secretion and increase in mucosal cyclic AMP content. 4. Pretreatment with morphine (5 mg/kg, s.c.) did not influence the effects of VIP on net water flux and on mucosal cyclic AMP content. 5. Atropine (2 mg/kg, s.c.) also failed to reduced the effect of VIP (0.4 x 10(-9) mol/min/kg) on net water flux. 6. Stimulation of adenylate cyclase activity was a function of VIP concentration over a range of 1 x 10(-10)-1 x 10(-7) M. Morphine (up to 1 x 10(-3) M) failed to influence stimulation of adenylate cyclase by VIP. 7. The finding that low doses of VIP, which already have an effect on net water flux, fail to increase cyclic AMP levels makes it likely that other mediators besides cyclic AMP are involved in the effect of VIP on net water flux. Some of the present results, however, support the assumption that VIP stimulates intestinal fluid secretion by increasing mucosal cyclic AMP levels.     

吗啡对体外培养人乳腺纤维细胞和成骨细胞的影响

目的研究吗啡对体外培养的人乳腺纤维细胞、成骨细胞增殖效应的影响,以及离体细胞在该效应中雌激素受体（ER）及阿片受体（MOR）的变化。方法体外培养人正常乳腺纤维细胞、成骨细胞,将培养好的细胞分为对照组、递增剂量吗啡组M1（1×10-5mol/L）、M2（1×10-6mol/L）、M3（1×10-7mol/L）、吗啡＋纳洛酮组（M＋N）、17-β雌二醇＋吗啡（E＋M）;观察细胞增殖效应,反转录聚合酶链反应（RT-PCR）半定量测定ERmRNA和MORmRNA的表达。结果乳腺纤维细胞、成骨细胞体外培养,加入吗啡后行细胞计数表现出细胞增生降低,吗啡干预组ERmRNA和MORmRNA均下降;该作用在加入纳洛酮后会得到缓解。结论吗啡可直接抑制离体培养的正常乳腺纤维细胞、成骨细胞的增殖,该作用可能通过影响MOR,并下调ER表达发挥作用。     

Modulation by oxytocin of ATP-activated currents in rat dorsal root ganglion neurons

The modulatory effect of oxytocin (OT) on ATP-activated currents (I(ATP)) was studied in freshly isolated dorsal root ganglion (DRG) neurons of rats using whole cell clamp technique. In most of the neurons examined (50/70, 71.4%) extracellular application of OT (10(-9)-10(-5) mol/L) suppressed I(ATP) while in the rest (20/70, 28.6%) no modulatory effect was observed. OT shifted the ATP concentration-response curve downwards with a decrease of 39.8+/-4.2% in the maximal current response and with no significant change of Kd value. This OT-induced inhibition of I(ATP) showed no voltage dependence, and could be blocked by [d(CH(2))(5),Tyr(Me)(2),Thr(4),Tyr-NH(2)(9)]-OVT (d(CH(2))(5)-OVT) (10(-8) mol/L), a specific OT receptor antagonist. Intracellular application of H-9 (4 x 10(-5) mol/L, an inhibitor of protein kinase A) (n=12), BAPTA (10(-2) mol/L, a chelator of calcium ions) (n=4) could reverse the inhibitory effect of extracellular OT (10(-7) mol), while inclusion of H-7 (2 x 10(-5) mol/L, a protein kinase C inhibitior) (n=8) and KN-93 (10(-5) mol/L, an inhibitor of CaMKII) (n=9) in the recording pipette did not affect this effect. The results suggested that OT inhibition on ATP-activated currents was mediated by OT receptors in the membrane of DRG neurons; and this inhibitory effect involved the transduction of intracellular cAMP-PKA and Ca(2+).