肝癌组织中诱导型一氧化氮合酶的表达

为了解诱导型一氧化氮合酶(induce nitricoxide synthase,iNOS)在肝癌发病中的作用,用免疫组织化学方法检测了肝癌组织中iNOS的表达。32例肝癌和10例正常肝组织进行HE染色、iNOS检测。10例正常肝组织内均未见iNOS阳性信号。肝癌组织iNOS表达高于正常对照肝组织(26/32vs 0/10,x2=31.328,P<0.01)。肝癌组织和癌旁肝组织均表达iNOS(23/32vs 25/32,x2=0.333,P=0.564)。iNOS通过多种途径参与肝癌的发病。     

人胃癌组织中一氧化氮合酶的表达

目的探讨NOS与胃癌的关系.方法用NADPH-d组织化学法测定了正常胃组织、癌旁组织和癌组织中一氧化氮合酶(NOS)表达水平.结果正常胃组织中粘膜上皮细胞、各种有分泌功能的细胞及肌层神经纤维中均有NOS表达,测一个视野NOS阳性细胞的平均灰度,正常胃组织为112、癌旁组织为120、胃癌组织为145.各组间差异有显著意义.表明正常胃组织NOS活性最高,胃癌组织NOS活性最低.结论①正常胃组织有广泛的NOS分布,提示NO对维持正常胃功能具有重要作用;②胃粘膜细胞癌变过程中,NOS活性明显降低,提示NOS活性与胃粘膜细胞癌变有高度相关性.     

人体肺癌组织一氧化氮合酶的表达及其与细胞周期的关系

目的　研究人体肺癌组织中一氧化氮合酶各亚型的表达及其与肺癌进展、肿瘤细胞增殖周期的关系。方法　采用免疫组织化学方法及流式细胞技术检测 2 4例人体肺癌组织中一氧化氮合酶三种亚型的表达情况及细胞增殖周期的变化 ,免疫组化染色强度用计算机自动图像分析系统进行处理。结果　肺癌组织中有三种亚型的一氧化氮合酶的表达 ,以 NOS1 和 NOS3表达为主 ,NOS1 和 NOS3在临床一二期肺癌的表达高于三四期肺癌 (P<0 .0 0 1 ) ,在无淋巴结转移者的表达高于淋巴结转移者 (P<0 .0 2和 P<0 .0 0 1 ) ,NOS1 表达阳者肺癌细胞增殖周期中 G1 S期的比例高于染色阴性者 (P<0 .0 5)。结论　 NOS尤其是 NOS1 和 NOS3在肺癌组织中的表达可以抑制肺癌的进展。     

诱导型一氧化氮合酶与寄生虫感染

一氧化氮(NO)在体内由L-精氨酸在一氧化氮合成酶(NOS)的催化下生成.它是一种重要的信使分子,参与血管、气道平滑肌的调节,神经递质的传递、细胞杀伤、肿瘤细胞的溶解及内分泌激素的释放过程,与许多疾病的发生、发展密切相关;既在机体多个系统多种细胞中具有广泛的生理功能,又可能参与多种疾病的发生过程.     

醛固酮对血管外膜诱导型一氧化氮合酶/一氧化氮通路影响的实验研究

目的观察醛固酮对血管外膜诱导型一氧化氮合酶（iNOS）／一氧化氮（NO）通路的影响及作用机制。方法取sD大鼠胸主动脉外膜,分别给予不同浓度醛固酮（ALD）10^-8～10^-6mol／L、ALl）＋螺内酯以及ALD＋RU486进行孵育,此外在给予脂多糖激活血管外膜iNOS／NO的情况下,观察以上各组药物刺激后iNOS／NO系统的变化。与上述药物共同孵育6h后通过Griess法测定相对稳定的代谢产物硝酸盐和亚硝酸盐（NOx）代表NO的产生量,采用[^3H]-L-精氨酸标记的同位素法测定外膜iNOS活性。结果（1）NOx产生的变化：ALD刺激后血管外膜NOx生成无明显变化。用螺内酯拮抗盐皮质激素受体后,高浓度ALD组（10～～10^-6mol／L）血管外膜NOx产生呈下降趋势（P〈0．05）。用RU486拮抗糖皮质激素受体后随ALD浓度增加NOx生成量也呈浓度依赖性增加（P〈0．01）。脂多糖刺激后上述趋势更为明显。（2）iNOS活性的变化：ALD刺激后iNOS活性无明显变化,螺内酯刺激后血管外膜iNOS活性有下降趋势,但无统计学意义。而RU486刺激后血管外膜iNOS活性显著增加（P〈0．05）。同时给予脂多糖刺激后,螺内酯＋ALD组血管外膜iNOS活性显著下降（P〈0．01）,ALD＋RU486组血管外膜iNOS活性显著增加（p〈0．05）。结论ALD主要通过盐皮质激素受体和糖皮质激素受体通路两种途径直接影响血管外膜iNOS／NO系统,醛固酮作用于盐皮质激素受体能够诱导iNOS激活、刺激NO产生,作用于糖皮质激素受体抑制iNOS／NO激活。     

肝病患者一氧化氮合酶表达异常及其临床意义

目的 探讨肝病患者抗氧化能力及一氧化氮合酶（NOS） 表达的临床价值。方法 收集26例急性肝炎（AH）、36例慢性肝炎（CH）、13例肝炎后肝硬化（LC）和23例原发性肝癌（HCC）患者的血清,分别检测其总抗氧化能力（TAO）、NOS浓度及一氧化氮（NO）水平,分析它们在肝脏疾病中的改变机制。结果 患者血清TAO在AH、CH中异常率为80％,在LC和HCC为50％;血清中NOS活性在肝病患者中的异常率在70％ 左右;NO水平在AH、CH和LC中异常率为70％,HCC组为48％。AH组、CH组TAO平均水平明显高于对照组,但LC和HCC组的差异不明显;肝病患者NO和NOS平均浓度显著高于对照组,但HCC患者NOS和NO平均浓度均低于AH、CH和LC组患者。结论 肝病患者血清NOS水平与NO浓度呈高度正相关,NO增加可能 对肝细胞起保护作用。     

原发性肝癌血浆一氧化氮含量及组织中诱导型一氧化氮合酶的表达

一氧化氮(NO)是来源于内皮细胞的具有自由基性质的气体状的血管松弛因子,具有舒张血管、降低血压等作用[1-5].     

诱导型一氧化氮合酶与脑缺血

研究显示 ,诱导型一氧化氮合酶 (iNOS)及其所产生的NO参与了脑缺血后的病理生理学过程 ,在脑缺血不同阶段的级联反应中发挥着正负双重效应。文章对iNOS/NO促进细胞凋亡和神经发生的作用及其机制 ,iNOS选择性抑制剂对缺血性脑损伤的影响作了综述。     

辛伐他汀对脓毒症大鼠肺组织诱导型一氧化氮合酶表达的影响

目的:探讨辛伐他汀对脓毒症大鼠肺组织诱导型一氧化氮合酶(iNOS)表达的影响.方法:90只健康SD大鼠随机分为对照组(生理盐水2 mL静脉滴注)、内毒素(LPS)组(LPS 5 mg/kg,用生理盐水稀释至2 mL静脉滴注)、LPS+辛伐他汀(Sta)组(LPS 5mg/kg,Sta 20mg/kg,生理盐水稀释至2 mL静脉滴注),每组30只.分别在用药后2、4、6、12、24 h处死大鼠,取右肺下叶用RT-PCR法检测肺组织iNOS mRNA表达.结果:光镜下对照组各时点肺泡结构正常;LPS组2h出现炎症损伤,以6h最为显著;LPS+ Sta组中性粒细胞浸润较LPS组减轻.LPS组iNOSmRNA表达较对照组和LPS+ Sta组明显增高(均P＜0.05),6h达高峰,12 h开始下降;LPS+ Sta组各时点iNOSmRNA表达趋势同LPS组,但接近对照组水平(P＞0.05).结论:辛伐他汀能改善脓毒症时肺组织的病理性炎症损伤,辛伐他汀能减低脓毒症时肺组织iNOS mRNA的表达.     

食管鳞癌组织诱导型一氧化氮合酶和增殖细胞核抗原的表达及意义

目的探讨食管鳞癌组织诱导型一氧化氮合酶（iNOS）和增殖细胞核抗原（PCNA）的表达与食管癌临床病理因素的关系。方法用免疫组化法检测2009年1至4月山东省泰安市中心医院52例食管鳞癌组织和20例癌旁正常组织iNOS与PCNA的表达,计数PCNA标记指数（PCNA LI）。食管鳞癌组织及癌旁正常组织iNOS蛋白阳性表达率、PCNA LI比较分别采用χ2检验、t检验;食管癌组织iNOS阳性表达者与iNOS阴性表达者PCNA LI比较采用t检验;不同临床病理因素食管鳞癌组织iNOS蛋白表达、PCNA LI比较分别采用χ^2检验、t检验、方差分析,进一步两两比较采用SNK-q检验;食管鳞癌组织iNOS蛋白与PCNA蛋白表达的关联性分析采用χ^2检验。结果食管鳞癌组织iNOS阳性表达率、PCNA LI均高于癌旁正常组织,且差异均有统计学意义[63.5%（33/52）与10.0%（2/20）比较,χ^2=14.455,P〈0.01;（53.29±14.55）与（2.65±1.82）比较,t=24.593,P〈0.05]。食管癌组织中,iNOS阳性表达者的PCNA LI高于iNOS阴性表达者,且差异有统计学意义[（60.89±9.98）与（40.08±11.53）比较,t=6.842,P=0.000]。不同临床分期、分化程度、有无淋巴结转移患者的食管鳞癌组织iNOS蛋白表达差异有统计学意义（χ^2=9.372,P=0.025;χ^2=12.784,P=0.002;χ2=6.361,P=0.012）。随着食管鳞癌组织癌细胞分化程度的降低PCNA LI升高,中分化和低分化的食管鳞癌组织PCNA LI明显高于高分化的食管鳞癌（q=6.000、7.378,P均〈0.05）。有淋巴结转移的食管鳞癌组织PCNA LI高于无淋巴结转移的食管鳞癌组织,且差异有统计学意义[（56.26±13.14）与（45.21±15.62）比较,t=2.556,P=0.014]。iNOS的表达与PCNA的表达有关联（χ^2=20.022,P=0.000）。结论 iNOS与PCNA蛋白在食管鳞癌组织中均有较高的阳性表达,且表达有关联。两者可能存在共同的激活机制,iNOS和PCNA蛋白表达与食管癌的恶性进程有关。     

喉癌组织中Bcl-2及Bax基因表达的研究

目的　探讨 Bcl- 2和 Bax协同在喉癌中的表达及其与喉癌临床的相关性。方法　应用免疫组化技术 SP法 ,对 63例喉癌组织、 1 0例正常喉组织标本中 Bcl- 2及 Bax表达产物进行检测 ,并对喉癌病人进行术后随访分析。结果　 (1 )喉癌组织中 Bcl- 2的表达量明显高于正常喉组织 (P<0 .0 5) ;喉癌组织中 Bax的表达量明显低于正常喉组织 (P<0 .0 5) ;(2 )喉癌组织中有不同水平的 Bcl- 2蛋白过度表达和 Bax蛋白低表达 ,二者在统计学上呈负相关 (r=- 0 .332 ,P<0 .0 5) ;(3) Bcl- 2 / Bax表达阳性组与阴性组生存曲线有显著差异。结论　 Bax/ Bcl- 2显示出良好的相关性 ,二者比值失衡 ,导致或促进了喉癌的发生 ,Bax/ Bcl- 2可作为喉癌的早期诊断、预后的参考指标。     

iNOS/NO体系在慢性肝炎及肝硬化患者中的表达

目的:探讨内源性NO在慢性病毒性肝炎-肝硬化发展进程中的作用.方法:采用硝酸还原酶法比色测定外周静脉及门静脉血浆中iNOS活性,并用免疫组织化学和RT-PCR方法观察肝组织iNOS蛋白及RNA的表达.结果:在慢性肝炎患者及肝硬化患者门静脉血与外周血中iNOS活性与对照组相比均明显升高(F=102.793,25.052,P<0.01),且门静脉血iNOS活性增高更为明显.慢性肝炎组及肝硬化组中iNOS蛋白的灰阶值均低于正常对照组(F=46.796,P<0.05),表明iNOS表达增强.慢性肝炎组、肝硬化组iNOS mRNA的表达均分别显著高于正常对照组(F=26.832,P<0.01),且随着肝脏病变的加重表达逐渐增加.结论:iNOS/NO体系在慢性肝炎-肝硬化发生发展中起着保持血管舒张状态的重要作用.     

高血压患者颅底血流速度改变与内皮素、一氧化氮关系的探讨

目的　研究血管内皮细胞合成分泌的血管活性物质内皮素 (ET)、一氧化氮 (NO)与高血压患者脑血流改变的关系。方法　测定 5 4例高血压患者与 2 0例非高血压患者血浆ET及NO水平 ,同时测定经颅多普勒血流。结果　①高血压组的颅底动脉收缩期峰值流速 (VS)及脉动指数(PI)明显高于对照组 (P <0 .0 5 ) ;②高血压病人血浆NO与颅底动脉血流速度呈负相关 (P <0 .0 2 ) ,ET与颅底动脉血流速度呈正相关 (P <0 .0 1) ;③高血压组血浆NO水平明显低于对照组 (P <0 .0 5 ) ,ET水平高于对照组 (P <0 .0 5 ) ,中重度高血压组NO水平低于轻度高血压组 (P <0 .0 5 ) ,ET水平高于轻度高血压组 (P <0 .0 5 )。结论　血浆ET和NO水平在一定程度上反映了高血压及其血管内皮损伤的程度     

家兔动脉粥样硬化与血小板源内皮型氧化氮合酶表达的相关性

Objective To explore the correlation of atheroselerosis progression and the expression of platelet derived endothelial nitric oxide synthase (eNOS) in rabbits. Methods A total of 24 male New Zealand white rabbits were used in this study. Six of the animals were fed with normal food (control group). Eighteen rabbits were fed with cholesterol-rich food (1 g/d) for 12 weeks to establish the atherosclerosis model. Among 18 models, 6 rabbits were executed immediately and their aorta and platelet samples were collected for further analysis (model group), 6 rabbits were orally administered with pravastatin (10 rag/d) for additional 12 weeks (treated group), and the remaining 6 rabbits were left untreated until the end of the study (untreated group). The control, treated and untreated animals were then killed, and the aorta and platelet samples were collected for eNOS expression analysis (RT-PCR). Results The aorta samples in model and untreated group exhibited rough intima and a lot of longitudinal fatty streaks, which indicated that atherosclerosis models were established successfully. While in treated group, the degree of atherosclerosis was decreased. The average percent of thickness of fatty streaks or atheroselerotic plaques relative to the whole thickness of vessel walls was 0. 04±0. 02, 0. 82±0. 16, 0. 33±0. 18,0. 77±0. 14 in control, model, treated and untreated group, respectively. The thickness of fatty streaks or atherosclerotic plaques was significantly increased in the model and untreated groups and decreased in treated group compared with the control group (both P<0. 05). The expressions of platelet derived eNOS/mRNA were 1. 02± 0. 28, 0. 41± 0. 27, 1.00 ± 0. 77, 0. 40±0. 29 in control, model, treated and untreated group, respectively. The expression of eNOS/mRNA was markedly decreased in model group and untreated group compared with the control group, but was increased in treated group compared with untreated and model groups (F=3. 544, P = 0. 024). Conclusions There is a negative correlation between eNOS expression and atherosclerosis development, which suggests that the reversal effect of pravastatin on atheroselerosis progression and plaque formation may relate to the expression of platelet derived eNOS.     

家兔动脉粥样硬化与血小板源内皮型氧化氮合酶表达的相关性

Objective To explore the correlation of atheroselerosis progression and the expression of platelet derived endothelial nitric oxide synthase (eNOS) in rabbits. Methods A total of 24 male New Zealand white rabbits were used in this study. Six of the animals were fed with normal food (control group). Eighteen rabbits were fed with cholesterol-rich food (1 g/d) for 12 weeks to establish the atherosclerosis model. Among 18 models, 6 rabbits were executed immediately and their aorta and platelet samples were collected for further analysis (model group), 6 rabbits were orally administered with pravastatin (10 rag/d) for additional 12 weeks (treated group), and the remaining 6 rabbits were left untreated until the end of the study (untreated group). The control, treated and untreated animals were then killed, and the aorta and platelet samples were collected for eNOS expression analysis (RT-PCR). Results The aorta samples in model and untreated group exhibited rough intima and a lot of longitudinal fatty streaks, which indicated that atherosclerosis models were established successfully. While in treated group, the degree of atherosclerosis was decreased. The average percent of thickness of fatty streaks or atheroselerotic plaques relative to the whole thickness of vessel walls was 0. 04±0. 02, 0. 82±0. 16, 0. 33±0. 18,0. 77±0. 14 in control, model, treated and untreated group, respectively. The thickness of fatty streaks or atherosclerotic plaques was significantly increased in the model and untreated groups and decreased in treated group compared with the control group (both P<0. 05). The expressions of platelet derived eNOS/mRNA were 1. 02± 0. 28, 0. 41± 0. 27, 1.00 ± 0. 77, 0. 40±0. 29 in control, model, treated and untreated group, respectively. The expression of eNOS/mRNA was markedly decreased in model group and untreated group compared with the control group, but was increased in treated group compared with untreated and model groups (F=3. 544, P = 0. 024). Conclusions There is a negative correlation between eNOS expression and atherosclerosis development, which suggests that the reversal effect of pravastatin on atheroselerosis progression and plaque formation may relate to the expression of platelet derived eNOS.     

家兔动脉粥样硬化与血小板源内皮型氧化氮合酶表达的相关性

Objective To explore the correlation of atheroselerosis progression and the expression of platelet derived endothelial nitric oxide synthase (eNOS) in rabbits. Methods A total of 24 male New Zealand white rabbits were used in this study. Six of the animals were fed with normal food (control group). Eighteen rabbits were fed with cholesterol-rich food (1 g/d) for 12 weeks to establish the atherosclerosis model. Among 18 models, 6 rabbits were executed immediately and their aorta and platelet samples were collected for further analysis (model group), 6 rabbits were orally administered with pravastatin (10 rag/d) for additional 12 weeks (treated group), and the remaining 6 rabbits were left untreated until the end of the study (untreated group). The control, treated and untreated animals were then killed, and the aorta and platelet samples were collected for eNOS expression analysis (RT-PCR). Results The aorta samples in model and untreated group exhibited rough intima and a lot of longitudinal fatty streaks, which indicated that atherosclerosis models were established successfully. While in treated group, the degree of atherosclerosis was decreased. The average percent of thickness of fatty streaks or atheroselerotic plaques relative to the whole thickness of vessel walls was 0. 04±0. 02, 0. 82±0. 16, 0. 33±0. 18,0. 77±0. 14 in control, model, treated and untreated group, respectively. The thickness of fatty streaks or atherosclerotic plaques was significantly increased in the model and untreated groups and decreased in treated group compared with the control group (both P<0. 05). The expressions of platelet derived eNOS/mRNA were 1. 02± 0. 28, 0. 41± 0. 27, 1.00 ± 0. 77, 0. 40±0. 29 in control, model, treated and untreated group, respectively. The expression of eNOS/mRNA was markedly decreased in model group and untreated group compared with the control group, but was increased in treated group compared with untreated and model groups (F=3. 544, P = 0. 024). Conclusions There is a negative correlation between eNOS expression and atherosclerosis development, which suggests that the reversal effect of pravastatin on atheroselerosis progression and plaque formation may relate to the expression of platelet derived eNOS.     

家兔动脉粥样硬化与血小板源内皮型氧化氮合酶表达的相关性

Objective To explore the correlation of atheroselerosis progression and the expression of platelet derived endothelial nitric oxide synthase (eNOS) in rabbits. Methods A total of 24 male New Zealand white rabbits were used in this study. Six of the animals were fed with normal food (control group). Eighteen rabbits were fed with cholesterol-rich food (1 g/d) for 12 weeks to establish the atherosclerosis model. Among 18 models, 6 rabbits were executed immediately and their aorta and platelet samples were collected for further analysis (model group), 6 rabbits were orally administered with pravastatin (10 rag/d) for additional 12 weeks (treated group), and the remaining 6 rabbits were left untreated until the end of the study (untreated group). The control, treated and untreated animals were then killed, and the aorta and platelet samples were collected for eNOS expression analysis (RT-PCR). Results The aorta samples in model and untreated group exhibited rough intima and a lot of longitudinal fatty streaks, which indicated that atherosclerosis models were established successfully. While in treated group, the degree of atherosclerosis was decreased. The average percent of thickness of fatty streaks or atheroselerotic plaques relative to the whole thickness of vessel walls was 0. 04±0. 02, 0. 82±0. 16, 0. 33±0. 18,0. 77±0. 14 in control, model, treated and untreated group, respectively. The thickness of fatty streaks or atherosclerotic plaques was significantly increased in the model and untreated groups and decreased in treated group compared with the control group (both P<0. 05). The expressions of platelet derived eNOS/mRNA were 1. 02± 0. 28, 0. 41± 0. 27, 1.00 ± 0. 77, 0. 40±0. 29 in control, model, treated and untreated group, respectively. The expression of eNOS/mRNA was markedly decreased in model group and untreated group compared with the control group, but was increased in treated group compared with untreated and model groups (F=3. 544, P = 0. 024). Conclusions There is a negative correlation between eNOS expression and atherosclerosis development, which suggests that the reversal effect of pravastatin on atheroselerosis progression and plaque formation may relate to the expression of platelet derived eNOS.     

家兔动脉粥样硬化与血小板源内皮型氧化氮合酶表达的相关性

Objective To explore the correlation of atheroselerosis progression and the expression of platelet derived endothelial nitric oxide synthase (eNOS) in rabbits. Methods A total of 24 male New Zealand white rabbits were used in this study. Six of the animals were fed with normal food (control group). Eighteen rabbits were fed with cholesterol-rich food (1 g/d) for 12 weeks to establish the atherosclerosis model. Among 18 models, 6 rabbits were executed immediately and their aorta and platelet samples were collected for further analysis (model group), 6 rabbits were orally administered with pravastatin (10 rag/d) for additional 12 weeks (treated group), and the remaining 6 rabbits were left untreated until the end of the study (untreated group). The control, treated and untreated animals were then killed, and the aorta and platelet samples were collected for eNOS expression analysis (RT-PCR). Results The aorta samples in model and untreated group exhibited rough intima and a lot of longitudinal fatty streaks, which indicated that atherosclerosis models were established successfully. While in treated group, the degree of atherosclerosis was decreased. The average percent of thickness of fatty streaks or atheroselerotic plaques relative to the whole thickness of vessel walls was 0. 04±0. 02, 0. 82±0. 16, 0. 33±0. 18,0. 77±0. 14 in control, model, treated and untreated group, respectively. The thickness of fatty streaks or atherosclerotic plaques was significantly increased in the model and untreated groups and decreased in treated group compared with the control group (both P<0. 05). The expressions of platelet derived eNOS/mRNA were 1. 02± 0. 28, 0. 41± 0. 27, 1.00 ± 0. 77, 0. 40±0. 29 in control, model, treated and untreated group, respectively. The expression of eNOS/mRNA was markedly decreased in model group and untreated group compared with the control group, but was increased in treated group compared with untreated and model groups (F=3. 544, P = 0. 024). Conclusions There is a negative correlation between eNOS expression and atherosclerosis development, which suggests that the reversal effect of pravastatin on atheroselerosis progression and plaque formation may relate to the expression of platelet derived eNOS.     

家兔动脉粥样硬化与血小板源内皮型氧化氮合酶表达的相关性

Objective To explore the correlation of atheroselerosis progression and the expression of platelet derived endothelial nitric oxide synthase (eNOS) in rabbits. Methods A total of 24 male New Zealand white rabbits were used in this study. Six of the animals were fed with normal food (control group). Eighteen rabbits were fed with cholesterol-rich food (1 g/d) for 12 weeks to establish the atherosclerosis model. Among 18 models, 6 rabbits were executed immediately and their aorta and platelet samples were collected for further analysis (model group), 6 rabbits were orally administered with pravastatin (10 rag/d) for additional 12 weeks (treated group), and the remaining 6 rabbits were left untreated until the end of the study (untreated group). The control, treated and untreated animals were then killed, and the aorta and platelet samples were collected for eNOS expression analysis (RT-PCR). Results The aorta samples in model and untreated group exhibited rough intima and a lot of longitudinal fatty streaks, which indicated that atherosclerosis models were established successfully. While in treated group, the degree of atherosclerosis was decreased. The average percent of thickness of fatty streaks or atheroselerotic plaques relative to the whole thickness of vessel walls was 0. 04±0. 02, 0. 82±0. 16, 0. 33±0. 18,0. 77±0. 14 in control, model, treated and untreated group, respectively. The thickness of fatty streaks or atherosclerotic plaques was significantly increased in the model and untreated groups and decreased in treated group compared with the control group (both P<0. 05). The expressions of platelet derived eNOS/mRNA were 1. 02± 0. 28, 0. 41± 0. 27, 1.00 ± 0. 77, 0. 40±0. 29 in control, model, treated and untreated group, respectively. The expression of eNOS/mRNA was markedly decreased in model group and untreated group compared with the control group, but was increased in treated group compared with untreated and model groups (F=3. 544, P = 0. 024). Conclusions There is a negative correlation between eNOS expression and atherosclerosis development, which suggests that the reversal effect of pravastatin on atheroselerosis progression and plaque formation may relate to the expression of platelet derived eNOS.