体外培养中IFN-γ、L-Arg 及L-NNA对NO合成的影响及NO抗旋毛虫的作用

目的　探讨体外培养中IFN γ、L Arg及L NNA对NO合成的影响及NO抗旋毛虫的作用。 方法　分离、纯化长爪沙鼠腹腔巨噬细胞 ,置RPMI16 4 0培养液中培养。设IFN γ组、L Arg组、L NNA组和对照组 ,每个实验组又分 5个不同的浓度组。分别向含有巨噬细胞的培养瓶中加入不同浓度的IFN γ、L Arg及L NNA进行体外培养。培养 2 4h后 ,用硝酸还原酶法分别测定培养液中的NO含量。将旋毛虫幼虫分别加入上述培养体系中进行体外培养 ,观察旋毛虫幼虫的活动及损伤。结果　①体外培养中 ,激活的巨噬细胞能产生NO ,IFN γ和L Arg能促进NO的合成 ,L NNA则能抑制NO的合成 ,这种促进或抑制NO合成的作用均具有剂量依赖性 ,剂量越高作用越明显。②加入旋毛虫幼虫后 ,在IFN γ和L Arg培养体系中 ,随着NO浓度的升高及作用时间的延长 ,对虫体的抑制及杀伤作用越来越明显 ,导致其活动度减弱 ,虫体破裂 ,最终死亡 ;在L NNA培养体系中 ,L NNA浓度越高 ,对虫体的影响越小。结论　①体外培养中 ,通过激活的巨噬细胞 ,IFN γ和L Arg能促进NO的合成 ,给予L NNA则能抑制NO的合成。②NO对旋毛虫幼虫有抑制及杀伤作用     

NO对兔局灶脑缺血脑水肿和脑梗塞灶的影响

本文在兔MCAO局灶脑缺血模型基础上,利用外源性一氧化氮(NO)前体物质L-精氨酸和NOS抑制剂L-NNA研究NO对脑缺血后脑水肿和脑梗塞的影响。NZW兔42只随机分为7组,每组6只,计对照组、假手术组、MCAO组、MCAO+NS组、MCAO+L-Arg组、MCAO+D-Arg组及MCAO+L-Arg+L-NNA组。结果提示:与单纯MCAO组比较,L-Arg组的脑组织H_2O、Na~+、Ca~(2+)含量明显下降(P<0.01),脑梗塞灶亦明显缩小(P<0.01)。从而显示L-Arg系通过产生NO促使血管舒张而减轻脑水肿和缩小梗塞灶,为临床改进脑缺血的治疗提供依据。     

Nitric oxide mediates intestinal hyperaemic responses to intraluminal bile-oleate

It has long been recognized that intestinal blood flow increases at mealtimes. Mesenteric hyperaemia is also evoked by activation of sensory peptidergic nerves. Our studies explored the possible role of endogenous nitric oxide (NO) in the rat intestinal vasodilator response to luminal instillation of an oleic acid plus bile mixture before and after acute intrajejunal instillation of capsaicin and after chronic pretreatment with capsaicin. In anaesthetized rats we measured jejunal blood flow (BF) with an ultrasonic Doppler flowmeter and systemic arterial pressure (AP) with a pressure transducer. Intestinal perfusion with 80 mM oleic acid in bile increased BF by 98±12%. Instillation of 4 mg of capsaicin into the jejunal lumen initially increased BF by 42±9% but was followed by vasoconstriction. Inhibition of NO synthase with 25 mg/kg i.v. N-nitro-L-arginine (L-NNA) decreased BF by 27±5% and increased AP by 37±11%. After treatment with L-NNA and after acute and chronic administration of capsaicin, the bile-oleate-induced maximal increases in BF above control levels were 42±7%, 65±12%, and 58±8%, respectively. The observed inhibitory effect of L-NNA on the intestinal hyperaemic response to the bile-oleate mixture was reversed by pretreatment with L-arginine (100 mg/kg i.V.). In capsaicin pretreated rats the subsequent bile-oleate-induced hyperaemia was reduced in magnitude but the inhibitory effects of L-NNA were proportionately the same as in animals not receiving capsaicin. These findings support the hypothesis that NO is involved with bile-oleate-induced mesenteric hyperaemia.     

大鼠体内硝基精氨酸的手性代谢动力学

目的　应用毛细管电色谱 (CEC)对大鼠体内的硝基精氨酸手性转化和代谢动力学进行研究。方法　采用手性配体交换法检测大鼠血浆中D型硝基精氨酸 (D NNA)和L型硝基精氨酸(L NNA)的浓度,应用非房室模型对所获得的血药浓度-时间数据进行拟合,计算药动学参数。结果　D NNA和L NNA在大鼠体内代谢具有明显的异构体选择性,清除率分别为(0 46±0 02)ml·h-1·kg-1和(0 17±0 03)ml·h-1·kg-1 (P<0 05 );T1 /2分别为 ( 1 44±0 28 )h和(3 48±0 41)h(P<0 05)。D NNA到L NNA的单项手性转化率为(50 03±8 5)%。结论　D NNA和L NNA在大鼠体内的代谢有明显的异构体选择性 (其差异可能主要源于D NNA到L NNA的单向手性转化)。     

络活胶囊对高血压大鼠血浆肾上腺髓质素和组织因子途径抑制物的影响

采用腹腔注射左旋硝基精氨酸造成的大鼠高血压模型 ,对络活胶囊的降压机制进行研究。模型组、对照组、络活 1、2、3组各组应用左旋硝基精氨酸后 1、2周 ,心率明显减慢。药后各用药组血压均有所下降 ,与用药前比较有明显差异 ;与模型组比较 ,也有显著性差异 (P <0 .0 1)。各用药组用药后心率明显加快 ,与药前比较均有显著性差异 (P <0 .0 1) ,用药后ADM水平均有所升高 ,与用药前比较无显著性差异 ,但有升高趋势。络活 2、3组和对照组的TFPI水平与空白组比较有明显差异 (P <0 .0 5 )。说明络活胶囊可以降低左旋硝基精氨酸造成的大鼠高血压 ,升高血浆ADM水平 ,降低血浆TFPI水平     

左旋硝基精氨酸抗大鼠海马脑片缺氧损伤的电生理研究

目的 :为进一步证实一氧化氮合酶 ( NOS)抑制剂左旋硝基精氨酸 ( L -NNA)抗缺血缺氧性脑损伤的作用。方法 :在大鼠离体海马脑片 ,用电生理记录技术 ,观察 L-NNA对缺氧时海马脑片顺向群峰电位 ( OPS)的影响。结果 :使用 L-NNA的海马脑片缺氧后 OPS的恢复程度和恢复率分别为 10 4.79± 6 6 .2 5 %、75 .0 0 % ,与对照组相比有显著性差异 ( P<0 .0 5 )。结论 :L-NNA有明显抗缺氧脑损伤作用 ,作用机理可能是 L -NNA抑制了 n NOS活性 ,降低缺氧时神经源性 NO的形成 ,减轻 NO对神经细胞的毒性作用     

Kudzu root: traditional uses and potential medicinal benefits in diabetes and cardiovascular diseases

Kudzu root (Gegen in Chinese) is the dried root of Pueraria lobata (Willd.) Ohwi, a semi-woody, perennial and leguminous vine native to South East Asia. It is often used interchangeably in traditional Chinese medicine with thomson kudzu root (Fengen in Chinese), the dried root of P. thomsonii, although the Chinese Pharmacopoeia has separated them into two monographs since the 2005 edition. For more than 2000 years, kudzu root has been used as a herbal medicine for the treatment of fever, acute dysentery, diarrhoea, diabetes and cardiovascular diseases. Both English and Chinese literatures on the traditional applications, phytochemistry, pharmacological activities, toxicology, quality control and potential interactions with conventional drugs of both species have been included in the present review. Over seventy phytochemicals have been identified in kudzu root, with isoflavonoids and triterpenoids as the major constituents. Isoflavonoids, in particular puerarin, have been used in most of the pharmacological studies. Animal and cellular studies have provided support for the traditional uses of kudzu root on cardiovascular, cerebrovascular and endocrine systems, including diabetes and its complications. Further studies to define the active phytochemical compositions, quality standards and clinical efficacy are warranted. Strong interdisciplinary collaboration to bridge the gap between traditional medicine and modern biomedical medicine is therefore needed for the development of kudzu root as an effective medicine for the management of diabetes and cardiovascular diseases.     

小鼠十二指肠运动中NO对NA作用的影响及机制

目的观察去甲肾上腺素(noradrenaline ,NA)对离体小鼠十二指肠肌条收缩幅度及一氧化氮(nitricoxide ,NO)对NA作用的影响;探讨NO和NA之间的关系及影响机制。方法用器官浴槽孵育离体小鼠十二指肠肌条,以肌张力收缩幅度抑制比为指标观察NA对肌条收缩幅度及NO对NA作用的影响。结果NA对肌条的收缩幅度有明显的抑制作用,在浓度1.2×10 -4～1.2×10 -8mol/L范围内,呈剂量-效应关系,其中1.2×10 -8mol/L组与对照组之间无显著性差异(P >0 .0 5 )。L Arg对肌条的收缩幅度有明显的抑制作用,在浓度2×10 -2 ～2×10 -6mol/L范围内,呈剂量-效应关系。除2×10 -6mol/L组外,其余各浓度的L Arg与对照组均有显著性差异(P <0 .0 0 1)。用无反应剂量2×10 -6和2×10 -3 mol/L的L Arg孵育标本后加入NA ,浓度为1.2×10 -5,1.2×10 -6,1.2×10 -7,1.2×10 -8mol/L的NA对肌条收缩幅度的抑制作用明显增强,与单独NA组的作用相比差异有显著性(P <0 .0 0 1) ;而1.2×10 -4mol/LNA组与单独NA组的作用相比差异无显著性(P >0 .0 5 )。分别用一氧化氮合酶(NOS)的抑制剂L NNA、可溶性鸟苷酸环化酶(sGC)抑制剂ODQ、α肾上腺素能受体阻断剂酚妥拉明(phentolamine)均使NA对肌条收缩幅度抑制效应明显减弱,与对照组比较有显著性差异(P <0 .0 0     

Anti-atherogenic effects of statins: Impact on angiopoietin-2 release from endothelial cells

Beyond lipid lowering, statins are supposed to exert pleiotropic effects positively influencing the progression of atherosclerotic lesions. The development of such lesions is associated with increased release of angiopoietin-2 (Ang-2), an endothelial cell-specific protein growth factor stored in Weibel-Palade bodies (WPBs). The aim of our study was to examine whether statin pretreatment influences the release of Ang-2 from endothelial cells. Stimulation of HUVECs and HMVECs with PMA, thrombin or histamine resulted in significant release of Ang-2, as evidenced by ELISA. Pretreatment with simvastatin and mevastatin suppressed this release to basal level, while pravastatin had no effect. Simvastatin itself increased nitric oxide (NO, EC number 1.14.13.39) synthesis, measured by Griess reaction. Combining the statin pretreatment with the eNOS inhibitor L-NNA as well as bypassing the HMG-CoA reductase (EC number: 1.1.1.34) by adding mevalonic acid or geranyl pyrophosphate restored the exocytotic effect of PMA. Immunofluorescence microscopy showed that depletion of WPBs upon PMA stimulation ceased after pretreatment with simvastatin. This study demonstrates a potent suppressive effect of statins on the release of Ang-2 from endothelial cells. Regarding its harmful effects in the development of atherosclerotic lesions, our data provide further insight into the mechanisms of the anti-atherogenic potential of statins.     

附子干姜合用丙磺舒、兰索拉唑对NOS抑制型高血压模型小鼠影响观察

目的 ：研究附子干姜合用丙磺舒、兰索拉唑对一氧化氮合酶（NOs）抑制型高血压模型小鼠的影响,并初步探讨其作用机制。方法：将雄性ICR小鼠随机分为空白对照组（C组）、左旋N-硝基精氨酸（L广NNA）模型组（M组）、L—NNA＋附子干姜组（FG组）、L-NNA＋丙磺舒组（B组）、L—NNA＋兰索拉唑组（L组）、L—NNA＋附子干姜＋丙磺舒组（FG＋B组）、L—NNA＋兰索拉唑＋丙磺舒组（L＋B组）、L-NNA＋附子干姜＋兰索拉唑＋丙磺舒组（FG＋L＋B组）。各组分别给予0．5％羧甲基纤维素钠（CMC-Na）溶液、L—NNA、L—NNA＋附子干姜水煎液3g／kg、L—NNA＋丙磺舒360mg／kg、L-NNA＋兰索拉唑30mg／kg、L-NNA＋附子干姜水煎液3g／kg＋丙磺舒360mg／kg、L—NNA＋兰索拉唑组30mg／kg＋丙磺舒组360mg／kg,L-NNA＋附子干姜水煎液3g／kg＋丙磺舒360mg／kg＋兰索拉唑30mg／kg。持续灌胃给药10天后测定各组小鼠的血压,检测血清、心、肝、肾和胃组织中的一氧化氮（NO）和丙二醛（MDA）含量。结果：与C组相比,M组、B组、L组和L＋B组血压显著升高（P〈0．01,P〈0．05,P〈0．05）,M组和B组大鼠的血清和心、肝、肾、胃中的N0含量下降,MDA含量升高（P〈0．01或P〈0．05）。与模型组相比,FG组、FG＋B组、FG＋B＋L组小鼠的血压和生化指标均有所改善（P〈0．01或P〈0．05）,其中FG＋B组死亡率最低,FG＋B＋L组其次。结论：FG组、FG＋B组、FG＋B＋L组药物均能升高NOS抑制型高血压小鼠的NO含量,降低MDA含量,从而产生降压、降低组织氧化损伤的作用,其中FG＋B＋L组小鼠更趋近于正常水平。