荆花胃康胶丸对胃溃疡大鼠胃黏膜的促愈合作用

目的:观察荆花胃康胶丸对实验性胃溃疡大鼠胃黏膜的促愈合作用。方法:100只SD大鼠建立胃溃疡模型,随机分成模型对照(给予生理氯化钠溶液)组、雷尼替丁30 mg·kg~(-1)·d~(-1)组、荆花胃康胶丸10,15和20 mg·kg~(-1)·d~(-1)组,每组20只,另取20只正常大鼠作为正常对照组。在造模后d 5各组开始灌胃给药或生理氯化钠溶液,bid,连续14 d。用游标卡尺测量溃疡指数(ulcer index,UI),用硝酸还原酶法测定胃黏膜NO含量,用ELISA法检测胃黏膜表皮生长因子(EGF)含量,用SABC免疫组化的方法检测胃黏膜表皮生长因子受体(EGFR)的表达。结果:与模型组比较,荆花胃康胶丸组UI值剂量依赖性的降低,血清和组织NO和EGF含量剂量依赖性的升高。荆花胃康胶丸组溃疡边缘组织EGFR阳性表达的细胞较模型组和正常对照组增多(P＜0．01)。结论:荆花胃康胶丸可能通过促进胃黏膜NO和EGF分泌,维持胃黏膜结构完整;通过上调上皮细胞EGFR表达,加速溃疡愈合。     

荆花胃康胶丸对溃疡大鼠胃黏膜及6-keto-PGF1α含量的影响

目的研究荆花胃康胶丸对Okabe氏溃疡模型大鼠胃黏膜愈合及溃疡组织6-酮-前列腺素F1α(6-keto-PGF1α)含量的影响.方法采用Okabe氏法,在大鼠胃前壁造成溃疡,随机将模型动物分为模型对照(生理氯化钠溶液)、荆花胃康胶丸大、中、小剂量(30,20,10 mg·kg-1·d-1)、硫糖铝10 mg·kg-1·d-1及法莫替丁5 mg·kg-1·d-1组,各组均灌胃给药,qd,连续10 d.给药结束后,计算各组大鼠溃疡面积和溃疡指数,测定溃疡组织黏膜缺损宽度及再生黏膜厚度,并定量检测胃组织的6-keto-PGF1α含量.结果与模型对照组相比,荆花胃康胶丸组剂量依赖性地降低溃疡面积和溃疡指数及黏膜肌层缺损宽度,增加再生黏膜厚度和大鼠胃组织6-keto-PGF1α的含量(P＜0.01);荆花胃康胶丸30 mg·kg-1组的作用优于硫糖铝组及法莫替丁组(P＜0.05).结论荆花胃康胶丸能促进溃疡愈合,其机制可能与增加溃疡组织6-keto-PGF的含量有关.     

荆花胃康胶丸对阿司匹林致小鼠胃黏膜损伤的修复作用

目的:探讨中药荆花胃康胶丸对阿司匹林所致小鼠胃黏膜损伤的修复作用.方法:建立阿司匹林所致小鼠急性胃黏膜损伤模型,观察中药荆花胃康胶丸(30mg·kg-1,ig)与胶体果胶铋胶囊(130mg·kg-1,ig)对胃黏膜损伤的修复作用,计算溃疡指数和溃疡抑制率.结果:中药荆花胃康胶丸能明显缩小阿司匹林烧灼引起的溃疡面积,溃疡指数较单纯损伤组显著降低(P＜0.05);与胶体果胶铋组比较,胃黏膜溃疡指数和溃疡抑制率无明显差异,保护作用相当.结论:中药荆花胃康胶丸对阿司匹林所致的小鼠胃黏膜损伤有较好的修复作用.     

二苯乙烯苷对动脉硬化大鼠主动脉一氧化氮合酶表达及舒张作用的影响

目的探讨二苯乙烯苷(TSG)对动脉粥样硬化大鼠主动脉一氧化氮合酶(NOS)表达的影响及对主动脉的舒张作用。方法SD大鼠65只,(?),随机分为6组:正常对照组、模型组、辛伐他汀组、TSG 120 mg·kg~(-1)·d~(-1)组、TSG 60 mg·kg~(-1)·d~(-1)组及TSG 30 mg·kg~(-1)·d~(-1)组。采用高脂饲料喂饲+VitD_3复制大鼠动脉粥样硬化模型,造模12 wk后抽样检测大鼠主动脉,以大鼠动脉粥样硬化斑块形成为造模指标。经治疗6 wk后,分离主动脉,-70℃保存,Western blot检测主动脉组织中NOS含量,RT-PCR检测大鼠主动脉内皮型一氧化氮合酶(eNOS)和诱导型一氧化氮合酶(iNOS)mRNA表达,同时观察TSG对大鼠离体主动脉血管环内皮依赖性血管舒张作用的影响。结果与模型组相比,辛伐他汀组和TSG各剂量组均能显著增加主动脉组织eNOS表达及降低主动脉组织iNOS表达,并呈剂量依赖性。TSG抑制去甲肾上腺素(NA)诱发的内皮依赖性血管收缩、增强乙酰胆碱(Ach)内皮依赖性血管舒张;TSG的血管舒张作用可被NO前体物L-精氨酸增强,而NOS抑制药L-硝基精氨酸甲酯可部分削弱之。结论TSG能上调其主动脉eNOS和下调iNOS表达,并能使内皮依赖性血管舒张,这可能与TSG抗AS作用的机制有关。     

荆花胃康胶丸治疗Hp相关性疾病的临床观察

目的观察荆花胃康胶丸治疗Hp相关性疾病的临床疗效。方法选取慢性浅表性胃炎、慢性萎缩性胃炎、十二指肠球部溃疡、胃溃疡及复合性溃疡患者116例。胃康胶丸治疗组80例,160mg,每日3次,28d为1疗程;对照组36例,法莫替丁20mg/次,每日2次,阿莫西林1.0,每日2次,克拉霉素0.5,每日2次,7d后,单用法莫替丁20mg/次,每日2次,共28d。对2组的临床症状改善情况、胃镜检查结果及幽门螺杆菌(Hp)根除进行比较。结果荆花胃康对上述慢性胃十二指肠疾病具有较好的疗效,患者自觉症状减轻,部分患者Hp转阴,胃镜检查病变明显好转。结论荆花胃康能有效治疗Hp相关性疾病,对Hp的根除有较好的作用。     

西地那非对脂多糖诱导的小鼠急性肺损伤的作用

目的明确西地那非对急性肺损伤(ALI)的治疗作用及可能机制。方法采用脂多糖(LPS,4 mg·kg~(-1))气道滴入诱导的小鼠ALI模型。随机分为生理盐水组、LPS模型组、西地那非3,10及30 mg·kg~(-1)组、地塞米松5 mg·kg~(-1)组。测定肺干/湿重比值,常规细胞形态学检测支气管肺泡灌洗液(BALF)中白细胞,肺组织切片观察病理改变;测定肺组织匀浆髓过氧化酶(MPO)活性、NO含量、NOS活性及TNF-α含量。结果LPS诱导的ALI小鼠肺干/湿重比值明显下降;BALF中白细胞总数及中性粒细胞比例明显增加;肺毛细血管通透性明显增加;肺组织间隙大量中性粒细胞浸润和红细胞渗出;肺组织匀浆TNF-α含量和MPO活性明显增加,NO含量、总NOS活性及iNOS活性明显增加。同时腹腔注射西地那非可剂量依赖性地降低ALI小鼠肺干/湿重比值;减少BALF中的白细胞总数及中性粒细胞的比例;降低肺毛细血管通透性;改善肺组织病理变化;抑制肺组织匀浆TNF-α含量、MPO活性及NO含量、总NOS活性及iNOS活性的增加。结论西地那非对LPS诱导的ALI有保护作用,提示NO- cGMP途径可能在ALI中起重要作用。     

荆花胃康胶丸与三联药物联合治疗根除胃十二指肠溃疡患者幽门螺杆菌

目的 幽门螺杆菌(Helicobacter pylori,HP)是胃十二指肠溃疡的重要病原,荆花胃康胶丸有抗菌活性,本文对荆花胃康胶丸与三联药物治疗根除胃十二指肠溃疡患者幽门螺杆菌效果进行比较.方法 伴有HP感染150例胃十二指肠患者,随机分成3组:①三联组(triple therapy,TT)50例,药物为克来霉素、阿莫西林、奥米拉唑;②荆花胃康胶丸组(JH)50例,药物为荆花胃康胶丸;③荆花胃康胶丸+奥米拉唑组(JTT)50例.4周后检测HP感染判断HP清除情况.结果 3组HP 清除率分别为74%、62%、90%.JTT组HP清除率明显优于其他两组(P<0.05),具有统计学意义.临床症状改善相似.结论 荆花胃康胶丸具有抗HP活性,与西药合用有协同作用.     

尼美舒利对吲哚美辛诱导的大鼠胃黏膜损伤的保护作用

目的探讨尼美舒利对胃黏膜的保护作用及其可能的作用机制。方法大鼠禁食12h后,ig给予吲哚美辛30mg·kg-1制备急性胃黏膜损伤模型,5min后分为模型对照、尼美舒利100mg·kg-1、塞来昔布100mg·kg-1、美洛昔康4mg·kg-1、双氯芬酸钠50mg·kg-1和布洛芬600mg·kg-1组,分别ig给予相应药物;另设正常对照组。6h后处死所有大鼠,测定胃溃疡面积。生化比色法检测大鼠胃组织和血清中谷胱甘肽(GSH)和丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性。结果正常对照组大鼠胃黏膜表面光滑,黏膜皱襞纹理清晰;模型组大鼠均见急性胃溃疡,溃疡面积为(10.6±7.4)mm2;与模型组比较,尼美舒利和塞来昔布组胃溃疡面积显著减小,分别为4.1±1.7和(4.9±3.2)mm2(P<0.01);美洛昔康组未见明显变化,为(8.1±3.5)mm2;双氯芬酸钠和布洛芬组胃溃疡面积明显增加,分别为15.4±4.8和(16.0±7.3)mm2(P<0.01)。与正常对照组比较,模型组大鼠胃组织中GSH含量和SOD活性明显降低(P<0.05),MDA含量显著升高(P<0.01);血清中MDA含量显著升高(P<0.01),而GSH含量和SOD活性变化不明显。与模型组相比,尼美舒利组胃组织中GSH含量和SOD活性明显升高(P<0.05,P<0.01),MDA含量明显降低(P<0.01);血清中GSH含量明显增加(P<0.01),MDA含量明显降低(P<0.01);塞来昔布组大鼠胃组织中SOD活性明显升高(P<0.01),血清中MDA含量明显降低(P<0.01),其他指标无明显变化;美洛昔康、双氯芬酸钠和布洛芬对模型大鼠胃组织和血清中GSH,MDA含量及SOD活性均无明显影响。结论尼美舒利对吲哚美辛诱导的大鼠急性胃黏膜损伤具有明显的保护作用,作用机制可能与其抗氧化活性有关。     

nobiliside A隐形纳米脂质体对小鼠RM-1前列腺癌的抑制作用

目的比较nobiliside A隐形纳米脂质体(NASNL)和nobiliside A普通脂质体(NACL)对小鼠RM-1前列腺癌的抑制作用。方法 RM-1前列腺癌荷瘤小鼠随机分为6组(均n=10):阴性对照组(生理盐水)、阳性对照组(环磷酰胺20 mg·kg~(-1)·d~(-1))、NACL低、高剂量组(1 mg·kg~(-1)·d~(-1)、2 mg·kg~(-1)·d~(-1))和NASNL低、高剂量组(1 mg·kg~(-1)·d~(-1)、2 mg·kg~(-1)·d~(-1)),均尾静脉注射给予相应药物,连续7 d。通过比较各组小鼠的肿瘤生长曲线、抑瘤率、肿瘤组织的病理变化等考察2种脂质体的抑瘤效果。结果 NASNL两剂量组的肿瘤生长速度均低于相应剂量的NACL组(P<0.05)。NASNL两剂量组的抑瘤率均高于相应的NACL组,其中NASNL高剂量组的抑瘤率是NACL高剂量组的2倍。NASNL各组肿瘤细胞坏死程度高于NACL各组。结论 NASNL的肿瘤抑制作用明显优于NACL。     

Kappa-晒化卡拉胶对实验动物的抗心律失常作用

Kappa-硒化卡拉胶是一含硒有机化合物。ip 9 mg·kg~(-1)·d~(-1)×5d或单次ig 35,70,140mg·kg~(-1)能显著提高乌头碱致大鼠HA的阈剂量,此作用可与Na_2SeO_3 1 mg·kg~(-1)·d~(-1)×5d ip比拟.随着Kappa-硒化卡拉胶ig剂量增加,尚可提高乌头碱所致VE,VT和VF的阈剂量。ip 9mg·kg~(-1)·d~(-1)×5 d或ig 70mg·kg~(-1)能提高BaCl_2致大鼠或哇巴因致豚鼠HA的阈剂量。对BaCl_2致大鼠VF或哇巴因致豚鼠VE的阈剂量,分别在ig70mg·kg~(-1)与140mg·kg~(-1)时有提高,而ipNa_2SeO_3 1 mg·kg~(-1)·d~(-1)×5d无此明显影响。     

大鼠脑出血周边组织NO含量和NOS活性变化及对细胞凋亡的影响

目的：研究大鼠脑出血周边组织一氧化氮(NO)含量和一氧化氮合酶(NOS)活性变化及与细胞凋亡的关系。方法：①Wistar大鼠104只，随机分为对照组、脑出血组、脑出血 氮硝基左旋精氨酸(NNLA)组，后两组各分为(4h、6h、12h、1d、3d、7d)6个时间点。②测定出血周边组织NO含量、NOS活性及神经细胞凋亡。结果：①大鼠脑出血周边组织NO、诱导型一氧化氮合酶(iNOS)，4h开始升高，3di NOS、NO达峰值。②大鼠脑出血周边组织6h出现凋亡，细胞3d凋亡细胞达峰值，与iNOS峰值对应，7d时仍存在较多凋亡细胞。③NNLA干预后NO含量、iNOS活性及凋亡细胞数量与脑出血组对应时间点比较显著下降，差异显著。结论：大鼠脑出血周边组织神经细胞存在长时间凋亡，NO、iNOS可以促进其凋亡，NOS抑制剂减少大鼠脑出血周边组织神经细胞凋亡。     

Role of nitric oxide produced by constitutive and inducible nitric oxide synthases in the mouse gastric fundus

In the present study, the role of nitric oxide (NO) produced by constitutive and inducible nitric oxide synthases (cNOS and iNOS, resepctively) on the contraction and relaxation of fundus in normal and lipopolysaccharide (LPS)-treated mice was examined. A whole fundic ring isolated from mice pretreated with reserpine was mounted in an organ bath containing Krebs' solution with 0.001 mmol/L atropine. Rings were contracted initially by 5-hydroxytryptamine (5-HT; 0.03 mmol/L) before relaxation was induced using ATP (0.03 mmol/L), ADP (0.03 mmol/L), pentoxifylline (0.002 mmol/L), electrical field stimulation (EFS; 50 V, 1 msec, 50 Hz, 3 min) and L-arginine (0.05 mmol/L). All drugs and EFS induced significant relaxation of isolated rings. The relaxations induced were significantly inhibited by N(G)-nitro-L-arginine methyl ester (L-NAME; 1.0 mmol/L). However, the iNOS inhibitors L-N(6)-(1-iminoethyl) lysine hydrochloride (L-NIL; 1.0 mmol/L) and amino guanidine (AMG; 1.0 mmol/L) had no significant effect on tissue relaxation. Then, the relaxant effects of 0.03 mmol/L ATP were tested on precontracted isolated fundic rings taken from 10 mg/kg LPS-treated animals. The non-selective NOS inhibitor L-NAME (10 mg/kg), the iNOS inhibitors L-NIL (3 mg/kg) and AMG (20 mg/kg) and betamethasone (0.1 mg/kg) were used to examine the role of NO produced by iNOS in the relaxation responses. It was found that the level of contraction induced by 0.03 mmol/L 5-HT in rings isolated from LPS-treated animals was significantly (P < 0.5) less than that in rings from untreated mice. However, precontracted tissues from LPS-treated mice were significantly relaxed by ATP and the relaxation response to ATP was significantly inhibited by L-NIL, ANG and betamethasone, but not by L-NAME. We suggest that, in LPS-treated mice, the production of NO from iNOS produces a reduction in the contractile response, as well as a decrease in NO formation by cNOS, resulting in changes to smooth muscle cell function.     

四逆汤对失血性休克家兔一氧化氮（NO）和一氧化氮合酶（NOS）的影响

目的：探讨中药四逆汤对失血性休克家兔一氧化氮的影响。方法：采用动物分组对照实验，测量不同状态下动物血浆一氧化氮和一氧化氮合酶(NOS)的变化。结果：与休克前比较，休克组的家兔血浆一氧化氮水平各时段均明显提高(P＜0．01)，而治疗组仅在治疗后30min家兔一氧化氮及NOS水平明显提高(P＜0．01)，其他时段与休克前比较，未见显著差异(P＜0．01)，且休克后lh、4h、8h休克组一氧化氮水平显著高于治疗组(P＜0．01)。经药物治疗的失血性休克家兔血浆一氧化氮水平明显降低。     

Involvement of nitric oxide in the inhibition of angiogenesis by interleukin-2

Interleukin-2 (IL-2), an immunoregulatory cytokine possessing antitumour activity, is an inducer of nitric oxide (NO) synthesis in mice and man. In this study, the possibility that IL-2 possesses antiangiogenic properties that account for its antitumour effects in vivo was examined. IL-2 caused a dose-dependent inhibition of angiogenesis in the chick embryo chorioallantoic membrane (CAM). This inhibition was completely reversed by the NO synthase inhibitor N^G-nitro-L-arginine methylester (L-NAME). Furthermore, IL-2 was capable of stimulating NO synthase activity in the CAM in vitro and this effect was suppressed by L-NAME. Addition of IL-2 to human umbilical vein endothelial cells (HUVECs) in culture, had no effect on their growth characteristics. These results suggest that IL-2 may be an important antiangiogenic molecule causing its effect via nitric oxide synthesis. The antiangiogenic activity of IL-2 may be, at least in part, responsible for its antitumour properties.     

大鼠对氟西泮抗痫耐受和依赖时海马中一氧化氮合酶的变化

目的通过测定大鼠对氟西泮抗痫耐受性和依赖性时海马中一氧化氮合酶(NOS)蛋白表达及活性的变化,探讨一氧化氮(NO)在此过程中可能的作用。方法建立大鼠对氟西泮抗痫耐受性和依赖性的模型。运用免疫印迹及免疫组化法检测海马中NOS蛋白表达,以及比色法检测NOS活性的变化。结果大鼠对氟西泮抗痫耐受组的海马中NOS蛋白表达明显高于对照组;而对氟西泮抗痫依赖组则与对照组差别无统计学意义。两组NOS活性均显著高于各自的对照组。结论NO可能是介导氟西泮抗痫耐受性和依赖性的因素之一。     

Effects of Nitro-L-Arginine on Blood Pressure and Cardiac Index in Anesthetized Rats: A Pharmacokinetic-Pharmacodynamic Analysis

Purpose. Nitric oxide synthase (NOS) inhibitors such as Nitro-L-arginine (L-NA) are being considered for the management of hypotension observed in septic shock. However, little information is available regarding the pharmacokinetic and pharmacodynamic properties of these agents. Our objective was to examine the relationships between L-NA plasma concentration and various hemodynamic effects such as cardiac index (CI), mean arterial pressure (MAP), and heart rate (HR) elicited by L-NA administration in rats. Methods. L-NA was infused at doses between 2.5 – 20 mg/kg/hr in anesthetized rats over one hour. Hemodynamic effects and plasma L-NA levels were determined. Results. Infusion of L-NA resulted in dose-dependent increases in MAP and systemic vascular resistance (SVR), decreases in CI, and minimal change in HR. The relationships between the hemodynamic effects and plasma L-NA levels were not monotonic, and hysteresis was observed. Using nonparametric analysis, the equilibration half-time (t_1/2,keo) between plasma L-NA and the hypothetical effect site was determined to be 51.5 ± 6.6 min, 42.4 ± 10.1 min, 43.4 ± 9.0 min for MAP, CI, and SVR, respectively (n = 14). The E_max and EC₅₀ values obtained were + 32.5 ± 8.4 and 2.6 ± 1.3 g/ml for MAP and –52.9 ± 15.6 and 3.7 ± 1.8 g/ml for CI, respectively. Conclusions. Although L-NA can bring about beneficial elevation of MAP, such effect is always accompanied by a stronger effect on CI depression. Dose escalation of L-NA may bring about detrimental negative inotropic effect and loss of therapeutic efficacy.     

Drug Discovery for Overcoming Chronic Kidney Disease (CKD): The Endothelin ETB Receptor / Nitric Oxide System Functions as a Protective Factor in CKD

Accelerated cardiovascular disease (CVD) is a frequent complication of renal disease. Chronic kidney disease (CKD) develops hypertension and dyslipidemia, which in turn can contribute to the progression of renal failure. There is general agreement that endothelin-1 (ET-1), which acts through the two subtypes of receptor ET_A and ET_B, plays important physiological roles in the regulation of normal cardiovascular function and that excessive ET-1 production is linked to CVD and CKD. Although selective ET_A or nonselective ET_A/ET_B receptor antagonisms have been recognized as a potential strategy for treatment of several cardiovascular disease, it remains unclear which of the antagonisms is suitable for the individuals with CKD because upregulation of the nitric oxide (NO) system via ET_B receptor is responsible for renal function such as natriuresis, diuresis, and glomerular hemodynamics. Our findings clearly indicate that the blockade of ET receptors, in particular ET_A-receptor antagonism, not only produces a potential renoprotective effect in CKD but also reduces the risk of CVD. In contrast, pharmacological blockade or genetic deficiency of ET_B receptor seems to aggravate CKD and CVD in several experimental models of rats. Moreover, preliminary evidence in patients with CKD also suggests that both selective ET_A- and nonselective ET_A/ET_B-receptor blockade decreases blood pressure but that selective ET_A blockade has additional desirable effects on renal hemodynamics. Thus, at least in CKD, these findings support the notion that ET_B receptor– mediated actions produce a renoprotective effect and that nonselective ET_A/ET_B-receptors blockade seem to offer no advantage over selective ET_A antagonism, and if anything may potentially reduce the benefits.     

L-arginine protects against stress-induced gastric mucosal lesions by preserving gastric mucus

1. We have shown that exogenously administered L-arginine protects against water immersion restraint (WIR) stress-induced gastric mucosal lesions in rats through preservation of nitric oxide (NO) generation via constitutive nitric oxide synthase (cNOS), but not inducible nitric oxide synthase (iNOS), in the gastric mucosa. We have also indicated that impaired gastric mucus synthesis and secretion occur through a decrease in gastric cNOS activity in WIR-stressed rats. Therefore, in the presesnt study, we examined whether exogenously administered L-arginine exerts a protective effect against WIR stress-induced gastric mucosal lesions in rats through preservation of gastric mucus synthesis and secretion by NO generated from the administered amino acid via cNOS in the gastric mucosa. 2. Rats were subjected to WIR stress for 3 and 6 h. Either L-arginine (150-600 mg/kg) or D-arginine (600 mg/kg) was injected intraperitoneally 0.5 h prior to WIR stress. Either N(G)-monomethyl L-arginine (L-NMMA; 100 mg/kg) or N(G)-monomethyl D-arginine (D-NMMA; 100 mg/kg) was injected subcutaneously 0.5 h prior to WIR stress. Total NOS, cNOS, iNOS, nitrite and nitrate (breakdown products of NO), hexosamine (an index of gastric mucin) and adherent mucus were assayed in the gastric mucosa. 3. Pretreatment with L-arginine, but not D-arginine, protected against gastric mucosal lesions in rats subjected to WIR stress for 3 and 6 h in a dose-dependent manner. Pretreatment with L-arginine, but not D-arginine, attenuated decreases in hexosamine and adherent mucus concentrations and cNOS activity and increases in total NOS and iNOS activities and nitrite/nitrate concentration in the gastric mucosal tissue of rats subjected to WIR stress for 3 and 6 h in a dose-dependent manner. Both the protective effect of L-arginine against gastric mucosal lesions and the attenuating effect of the amino acid on the decreases in gastric mucosal hexosamine and adherent mucus concentrations and cNOS activity in rats subjected to WIR stress for 6 h were counteracted by cotreatment with L-NMMA, a nitric oxide synthase inhibitor, but not D-NMMA. 4. These results suggest that exogenously administered L-arginine exerts a protective effect against stress-induced gastric mucosal lesions in rats at least partly through preservation of gastric mucus synthesis and secretion by NO produced from the administered amino acid via cNOS in gastric mucosal tissue.     

芍药苷对缺氧损伤内皮细胞产生NO、eNOS和细胞粘附分子的影响

目的:观察芍药苷对缺氧损伤的人脐静脉内皮细胞(HUVEC)产生一氧化氮(NO)、内皮型一氧化氮合酶(eNOS)和细胞粘附分子(ICAM-1、VCAM-1)的影响。方法:体外培养HUVEC,传至3代后,以不同浓度的芍药苷分别作用于HUVEC,同时进行缺氧处理。以硝酸还原酶法测定培养液上清中的NO,免疫细胞化学法检测内皮细胞eNOS的表达,细胞ELISA法测定细胞表面ICAM-1和VCAM-1的含量。结果:HUVEC在缺氧48h后产生NO的量显著减少(P<0.001),eNOS表达下调,而ICAM-1、VCAM-1表达上调;芍药苷可以剂量依赖性的增加内皮细胞NO生成量,上调eNOS的表达,下调ICAM-1、VCAM-1表达。结论:芍药苷可能通过增加HUVEC eNOS的表达增加NO的释放、抑制ICAM-1及VCAM-1的表达等途径对内皮细胞起保护作用。     

Angiostatin Inhibition of Vascular Endothelial Growth Factor– Stimulated Nitric Oxide Production in Endothelial Cells

Angiostatin (AS), a proteolytic fragment of plasminogen, is a potent antiangiogenic factor. It was reported that AS attenuates the vasodilatory response to vascular endothelial growth factor (VEGF) in isolated interventricular arterioles. Here, we investigated the effect of AS on nitric oxide (NO) production in human umbilical vein endothelial cells (HUVECs). AS inhibited VEGF-stimulated NO production in a dose-dependent manner, whereas AS alone did not affect basal NO production. Disruption of kringle structures by reduction of disulfide bonds resulted in the loss of the inhibitory effect of AS on VEGF-stimulated NO production. To elucidate how AS might impair VEGF activation of endothelial NO synthase (eNOS), we further examined whether AS would affect Ca²⁺-dependent and -independent pathways of eNOS activation. AS had no effect on the transient increase in cytosolic Ca²⁺ levels elicited by VEGF. In contrast, AS prevented VEGF-potentiated eNOS phosphorylation at Ser1177. These results clearly indicate that AS inhibits VEGF-stimulated NO production in HUVECs without affecting basal NO production. The kringle structures of AS are required for this effect, and impairment of Ser1177 phosphorylation of eNOS might be involved in the inhibition of VEGF-stimulated NO production by AS.