葛根素对去卵巢大鼠股骨及主动脉一氧化氮合酶亚型表达的影响

目的观察葛根素对去卵巢大鼠股骨及主动脉一氧化氮合酶（NOS）不同亚型表达的影响。方法3月龄雌性SD大鼠72只，随机分为6组：假手术组（SHAM）、去卵巢组（OVX）、17p雌二醇治疗组（ERT）、高剂量葛根素（PH）、中剂量葛根素（PM）和低剂量葛根素（PL）治疗组。去卵巢术后1w开始皮下注射给药，连续7w。硝酸还原酶法测定血清NO水平，免疫组化法分别观察股骨及主动脉内皮型NOS（eNOS）和诱导型NOS（iNOS）的表达。结果①与OVX组相比，PH、PM组大鼠血清NO水平显著提高（P〈0．01）；②在股骨及主动脉组织中，OVX组eNOS的表达明显减低（P〈0．01），各剂量葛根素组可不同程度地提高eNOS的表达（P〈0．01）；③iNOS的表达仅见于OVX大鼠股骨，其余各组大鼠股骨和各组大鼠主动脉均未见iNOS的明显表达。结论葛根素可以提高去势大鼠股骨及主动脉两组织中eNOS的表达，增加内源性NO的合成与释放，对防治绝经后妇女骨质疏松及动脉粥样硬化可能有益。     

神经病理性疼痛大鼠脊髓背角一氧化氮合酶各亚型的表达及活性变化

目的 比较神经病理性疼痛大鼠模型脊髓背角中神经型(nNOS),诱导型(iNOS)和内皮型(eNOS)三种一氧化氮合酶(NOS)的表达及活性变化.方法 雌性SD大鼠20只,150～200 g,随机均分为坐骨神经保留性损伤(SNI)组和对照组.SNI组大鼠于左后肢制备SNI模型,对照组大鼠暴露坐骨神经后立即缝合手术切口.术后观测疼痛的变化,于术后第14天断头处死大鼠,截取L4～6段脊髓,分离左右侧脊髓,于-80℃储存.SNI组和对照组各取5只大鼠脊髓,RT-PCR技术扩增nNOS、eNOS和iNOS片段,以β-actin作为内参照,比较SNI组与对照组NOS表达的相对差异.取两组另外5只大鼠脊髓冰上迅速匀浆,均取40 μg的蛋白,分别检测组成型NOS(cNOS,即nNOS和eNOS)和iNOS的活性.结果 SNI组手术侧nNOS、iNOS的mRNA表达均高于SNI组非手术侧和对照组手术侧(P<0.05),而eNOS的表达在SNI组手术侧、非手术侧和对照组手术侧之间差异并无统计学意义.NOS亚型催化活性检测显示SNI组手术侧iNOS和cNOS的活性均高于SNI组非手术侧和对照组手术侧(P<0.05).结论 神经病理性疼痛大鼠模型脊髓背角中iNOS的表达及其合成NO的活性均增加,可能促进了疼痛的发生,nNOS在疼痛中可能具有较强的调节能力.     

异丙酚对高血压大鼠胸主动脉内皮型一氧化氮合酶和诱导型一氧化氮合酶表达的影响

目的 评价异丙酚对高血压大鼠胸主动脉内皮型一氧化氮合酶(eNOS)和诱导型一氧化氮合酶(iNOS)表达的影响.方法 SD大鼠,雌雄各半,体重240～ 280 g,采用皮下注射去氧皮质酮的方法制备高血压模型,采用随机数字表法,将64只造模成功的大鼠随机分为4组(n＝16):高血压组(H组)、小剂量异丙酚组(P1组)、中剂量异丙酚组(P2组)和大剂量异丙酚组(P3组).P1组、P2组和P3组分别静脉输注异丙酚20、30、40 mg·kg-1·h-13 h,H组给予等容量生理盐水.分别于给药前、给药1h、3h时记录平均动脉压(MAP).给药3h时处死大鼠,摘眼球法采集血样,硝酸还原酶法测定血清一氧化氮(N0)浓度,取胸主动脉,采用RT-PCR和Western blot法测定eNOS mRNA、iNOS mRNA及其蛋白表达水平.结果 与H组比较,P1组、P2组和P3组给药3h时MAP降低,血清NO浓度升高,主动脉eNOS mRNA及其蛋白表达上调,主动脉iNOS mRNA及其蛋白表达下调,且呈剂量依赖性(P<0.05或0.01).结论 异丙酚降低高血压大鼠血压的机制与下调iNOS表达,上调血管内皮细胞eNOS表达,促进NO释放有关.     

神经源性膀胱组织中一氧化氮合酶表达的特点和意义

目的 探讨神经元型一氧化氮合酶(nNOS)、诱导型NOS(iNOS)和内皮型NOS(eNOS)在神经源性膀胱组织中表达状况,探讨一氧化氮在神经源性膀胱组织中产生及作用特点.方法 神经源性膀胱患儿30例.男18例,女12例.年龄(6.3±3.1)岁.30例均行手术治疗,术中留取膀胱组织标本,采用免疫组织化学方法检测膀胱组织中nNOS、iNOS和eNOS表达状况,10例正常膀胱组织标本作对照. 结果 正常膀胱体部组织nNOS阳性表达,走行在平滑肌纤维之间,分布于平滑肌细胞表面,膀胱基质也有表达,组织化学评分(HS)为2.8～4.0和1.2～2.7;平滑肌细胞iNOS阴性表达,平滑肌细胞基质有少量稀疏表达,HS为0～0.4和0～0.1;eNOS表达分布于血管内皮细胞中,分布稀疏,平滑肌细胞无表达.膀胱颈部组织表达高于膀胱体部组织,以nNOS表达为主.神经源性膀胱组织中以iNOS表达为主,nNOS表达明显减少;eNOS主要分布于膀胱基质的内皮细胞,膀胱平滑肌、成纤维细胞阴性表达;病变膀胱组织血管稀疏,微血管密度100倍视野下可见到(6.8±3.2)个血管灶,低于正常膀胱组织的(16.7±6.3)个(P＜0.01).结论 正常膀胱组织nNOS主要分布在膀胱颈中,NO合成主要受nNOS调节.神经源性膀胱患者膀胱组织中氮能神经元分布稀疏,nNOS表达减少,iNOS表达上调,NO的合成与调节可能主要来源于iNOS,受iNOS水平调节,eNOS表达下降,提示膀胱组织血供不良.     

一氧化氮和一氧化氮合酶在急性大面积脑梗死患者中的表达

目的 观察一氧化氮(NO)和一氧化氮合酶(NOS)在急性大面积脑梗死患者去骨瓣术后的表达.方法 急性大面积脑梗死患者16例(脑梗死组),均采用全麻开颅去骨瓣减压手术,手术中切除部分梗死额叶组织;以6例重型颅脑外伤行正常额叶组织内减压为对照组.2组均采用透视电镜观察额叶细胞超微结构,检测NO含量和NOS活性,Western blot法分析内皮型NOS(eNOS)、神经元型NOS(nNOS)和诱导型NOS(iNOS)蛋白表达特点.结果　本组病例16例脑梗死患者术后神志不同程度改善,无死亡病例;NO含量在脑梗死组和对照组分别为85.4U/ml和36.2U/ml,NOS活性在脑梗死组和对照组分别为63.2 μmol/L和37.2 μmol/L,差异均有统计学意义(P＜0.05);与对照组比较,eNOS、nNOS和iNOS在脑梗死组中表达均明显升高,尤其是iNOS表达相对值为0.76,远远超过对照组未见表达,差异均有统计学意义(P＜0.05).结论　去骨瓣减压是治疗急性大面积脑梗死的有效治疗手段,能够降低患者死亡率;NO和NOS参与并影响了大面积脑梗死后复杂的病理生理过程,去骨瓣减压后局部脑血供得到有效改善,NOS活性减低,尤其iNOS活性明显减少,合成NO减少,神经毒性减低,临床症状好转.

Abstract：

Objective To study the expression of nitric oxide (NO) and nitric oxide synthase (NOS) in patients with acute massive cerebral infarction. Methods Sixteen patients (cerebral infarction group) with acute massive cerebral infarction were subjected to craniotomy decompression craniectomy under the anesthesia, and part of the infarct frontal lobe was removed. The normal frontal lobe from 6 cases of severe brain injury receiving the intracranial decompression served as control group. The ultrastructures of frontal lobe cells were observed under the electron microscopy. Serum NO content and NOS activity were measured. The protein expression patterns of eNOS, nNOS and iNOS were analyzed by Western blotting.Results The consciousness in 16 patients with acute massive cerebral infarction was improved after operation to varying degrees, and there were no deaths. The NO contents and NOS activities in cerebral infarction group and control groups were 85.4 and 36. 2 U/mi, and 63.2 and 37.2 μmol/L ( all P ＜ 0. 05). As compared with control group, the expression of eNOS, nNOS and iNOS in cerebral infarction group was significantly increased, especially the expression of iNOS ( all P ＜ 0. 05). Conclusion Craniotomy decompression craniectomy was the effective treatment to cure the acute massive cerebral infarction. It could reduce mortality. NO and NOS participated in and influenced the complex pathophysiological process of massive cerebral infarction. After craniotomy decompression craniectomy the regional cerebral blood was effectively improved, and NOS activity, especially iNOS, and the synthesis of NO were reduced, resulting in the reduction to neurotoxicity and improvement in clinical symptoms.     

辛伐他汀预处理对脓毒症大鼠胸主动脉诱导型一氧化氮合酶及内皮型一氧化氮合酶表达的影响

目的 探讨辛伐他汀预处理对脓毒症大鼠胸主动脉诱导型一氧化氮合酶(iNOS)及内皮型一氧化氮合酶( eNOS)表达的影响.方法 清洁级雌性Wistar大鼠80只,4月龄,体重200～250 g,采用随机数字表法,将其随机分为4组:正常对照组(Ⅰ组,n=8)、假手术组(Ⅱ组,n=8)、脓毒症组(Ⅲ组,n=32)和辛伐他汀预处理组(Ⅳ组,n=32).Ⅱ组打开腹腔找到盲肠后还纳腹腔,缝合腹壁切口.Ⅲ组和Ⅳ组采用盲肠结扎穿孔法制备大鼠脓毒症模型.Ⅳ组制备脓毒症模型前经胃管灌注辛伐他汀20 mg/kg,1次/d,连续2周,Ⅰ组～Ⅲ组给予等容量生理盐水.Ⅱ组于假手术后6h处死动物,Ⅲ组和Ⅳ组于盲肠结扎穿孔后3、6、24、48 h分别取8只动物,处死,取胸主动脉,采用Western blot法测定iNOS和eNOS表达水平.结果 与Ⅰ组比较,Ⅱ组iNOS和eNOS表达差异无统计学意义(P＞0.05),Ⅲ组和Ⅳ组iNOS表达上调,eNOS表达下调(P＜0.05);与Ⅲ组比较,Ⅳ组iNOS表达下调,eNOS表达上调(P＜0.05).结论 辛伐他汀预处理可下调脓毒症大鼠血管内皮细胞iNOS表达和上调血管内皮细胞eNOS表达,对血管内皮细胞功能有保护作用.     

大鼠骨质疏松模型血清中一氧化氮和IL—6水平及意义

目的：测定骨质疏松模型大鼠血清中一氧化氮（NO）和IL－6水平，探讨其意义。方法：8月龄成年雌性SD大鼠随机分假手术对照组和去卵巢骨质 疏松模型组，术后第12周测量全身骨密度后处死，取血清用硝酸还原酶法测定NO水平，放免法测定IL－6和雌激素水平，结果：去卵巢骨质疏松模型组大鼠与假手术对照组相比，骨密度下降，胫骨骨小梁宽度变窄，间距变宽，小梁占视野面积比降低，血清中雌激素和NO含量显著下降，IL－6含量明显升高，大鼠骨密度与血清中雌激素和NO含量正相关，与IL－6含量负相关，结论：大鼠骨质疏松模型血清中NO水平降低，IL－6水平升高，NO和IL－6在骨质疏松的发生发展中起重要作用。     

大鼠睾丸内一氧化氮合酶的表达

目的 :阐明一氧化氮合酶 (NOS)在睾丸内的表达 ,探讨一氧化氮 (NO)在睾丸生殖功能中的作用。　方法 :取雄性SD大鼠睾丸于 4 %多聚甲醛中固定 ,常规石蜡切片。用免疫组化ABC法检测成年大鼠睾丸NOS的表达和定位。　结果 :内皮型NOS(eNOS)、神经型NOS(nNOS)、诱导型NOS(iNOS)在睾丸间质细胞内均有表达 ,精曲小管周围肌样细胞、血管内皮细胞和平滑肌细胞内仅为eNOS免疫反应阳性 ,而血管外膜纤维内仅有nNOS表达。免疫反应物质主要定位于细胞质 ,胞核为阴性。在生精细胞内 3种NOS免疫反应均为阴性。　结论 :3种NOS在睾丸内均有表达 ,不同的NOS分布部位有一定区别     

依普拉封对摘除卵巢所致大鼠骨质疏松的作用

本文研究了依普拉封对摘除卵巢所致雌性大鼠骨质疏松的治疗作用。摘除12个月龄雌性大鼠双侧卵巢，由于雌激素不足，造成骨质疏松。使用依普拉封尿钙排出降低，血清碱性磷酸酶活性升高、血清骨钙索含量增加。股骨X光片图像分析结果表明：依普拉封提高股骨远端骨骺端骨密度、骨干皮质厚度、皮质密度、骨干髓质密度及骨密度。同时，依普拉封可增加骨干重、灰重和骨钙含量。提示依普拉封可改善摘除卵巢大鼠所致的骨质疏松。     

一氧化氮、诱导性一氧化氮合酶在实验性大鼠腹主动脉瘤中的作用

目的:探讨一氧化氮(NO)和诱导性一氧化氮合酶(iNOS)在实验性大鼠腹主动脉瘤形成中的作用和机制.方法:建立大鼠腹主动脉瘤灌注模型,对照组予以生理盐水腹主动脉灌注,余下予以猪胰弹性蛋白酶灌注制作腹主动脉瘤模型,并分为实验组(术后腹腔注射生理盐水)、药物组(术后腹腔注射氨基胍),观察各组大鼠血清NO、腹主动脉瘤壁组织学和基质金属蛋白酶-9(MMP-9)、iNOS的变化.结果:生理盐水灌注组大鼠术前术后血清NO无明显变化,iNOS、MMP-9表达弱阳性或阴性,动脉壁炎性细胞浸润轻、弹性蛋白降解少;实验组血清NO显著升高,iNOS及MMP-9表达强阳性,炎性细胞浸润重、弹性蛋白几乎完全降解;应用氨基胍后iNOS变化不明显,而NO显著降低,MMP-9表达显著减弱,炎性细胞浸润和弹性蛋白降解明显减轻.结论:iNOS、MMP-9的表达和血清NO水平在实验组均显著升高.iNOS及其合成的NO能促进腹主动脉壁炎性细胞的浸润、中膜基质的降解和MMPs的表达,从而导致了腹主动脉瘤的生成.     

依普拉芬和雌激素对实验性骨质疏松作用的初步观察

目的：探讨依普拉芬和雌激素对绝经后骨质疏松症的防治作用。方法：将SD雌性大鼠32只随机分为4组,每组8只,I组：假手术组（Sham),Ⅱ组：切除卵巢组（OVX）,Ⅲ线：切除卵巢加雌激素组,Ⅳ组：切除卵巢加依普拉芬组。术后12周测定腰椎、股骨的骨密度：停药12周（即到术后24周）再行腰椎、股骨的骨密度测定及组织形态图像分析。结果：术后12周Ⅱ组大鼠体重增加明显与其他组差异有显性（P＜0.01),Ⅲ、Ⅳ两组之间无显性差异。术后24周Ⅲ、Ⅳ两组体重增加明显,与I组、Ⅱ组体重增加相比差异有显性（P＜0.05)。术后12周Ⅱ组腰椎、股骨骨密度下降明显,与Ⅲ、Ⅳ组差异有显性（P＜0.01);组织形态图像分析示Ⅳ组椎骨骨小梁面积增加,百分比增加,与Ⅱ组、Ⅲ组差异有显性（P＜0.001)。Ⅲ组、Ⅳ组股骨皮质骨厚度增加,骨小梁面积及百分比增加与Ⅱ组差异有显性（P＜0.001)。结论：依普拉芬和雌激素能有效地防止去势后大鼠的骨量丢失。依普拉芬有抑制骨吸收,又有促进骨形成的作用;其作用机理不同于雌激素。     

骨质疏松发生一氧化氮机制及雌激素调控作用研究

目的　研究骨质疏松发生的一氧化氮机制及雌激素防治骨质疏松作用的一氧化氮通路 ,深入理解骨质疏松症病理过程中一氧化氮作用环节。方法　 45只SD雌性大鼠分为①假手术组(Sham组 ) ;②卵巢切除组 (OVX组 ) ;③OVX +倍美力治疗 (Premarin组 )。进行iNOS原位杂交及iNOS、eNOS免疫组化研究 ,测定其平均灰度值及平均积分光密度 (ODI)作统计指标。结果　iNOS原位杂交实验结果显示 :正常大鼠去卵巢后 ,骨髓腔内及骨小梁表面iNOSmRNA有强阳性表达 ,差异有非常显著性 (P <0 0 1) ,iNOS免疫组化实验结果也显示OVX组iNOS阳性表达明显较Sham组增加 ;而Pre marin组iNOS表达强度较OVX组明显降低 (P <0 0 5 )。OVX组与Sham组eNOS表达差异无显著性 ,Premarin组较OVX组eNOS表达强度则明显增加 (P <0 0 5 )。结论　NO是调节OB、OC功能活动的一种重要效应因子 ,NO导致细胞因子诱导性骨吸收增强与绝经后雌激素缺乏OP密切相关。雌激素可下调iNOSmRNA表达 ,抑制iNOS蛋白合成 ,从而减轻功能亢进的OC性骨吸收 ,而对骨组织正常生理活动中的eNOS合成 ,有适度促进作用 ,有利于骨组织的重建及骨量的恢复 ,从而重建骨形成 吸收新平衡偶联     

Low-Intensity Electrical Stimulation Counteracts the Effects of Ovariectomy on Bone Tissue of Rats: Effects on Bone Microarchitecture,Viability of Osteocytes,and Nitric Oxide Expression

Low Intensity Electrical Stimulation (LIES) has been used for bone repair, but little is known about its effects on bone after menopause. Osteocytes probably play a role in mediating this physical stimulus and they could act as transducers through the release of biochemical signals, such as nitric oxide (NO). The aim of the present study was to investigate the effects of LIES on bone structure and remodeling, NOS expression and osteocyte viability in ovariectomized (OVX) rats. Thirty rats (200–220 g) were divided into 3 groups: SHAM, OVX, and OVX subjected to LIES (OVX + LIES) for 12 weeks. Following the protocol, rats were sacrificed and tibias were collected for histomorphometric analysis and immunohistochemical detection of endothelial NO synthase (eNOS), inducible NOS (iNOS), and osteocyte apoptosis (caspase-3 and TUNEL). OVX rats showed significant (p < 0.05 vs. SHAM) decreased bone volume (10% vs. 25%) and trabecular number (1.7 vs. 3.9), and increased eroded surfaces (4.7% vs. 3.2%) and mineralization surfaces (15.9% vs. 7.7%). In contrast, after LIES, all these parameters were significantly different from OVX but not different from SHAM. eNOS and iNOS were similarly expressed in subperiosteal regions of tibiae cortices of SHAM, not expressed in OVX, and similarly expressed in OVX + LIES when compared to SHAM. In OVX, the percentage of apoptotic osteocytes (24%) was significantly increased when compared to SHAM (11%) and OVX + LIES (8%). Our results suggest that LIES counteracts some effects of OVX on bone tissue preserving bone structure and microarchitecture, iNOS and eNOS expression, and osteocyte viability.      

大鼠肝缺血／再灌注后肝组织一氧化氮和不同亚型一氧化氮合酶的变化

目的探讨一氧化氮（NO）和一氧化氮合成酶（NOS）在肝缺血／再灌注（I／R）过程中的变化和作用。方法健康雄性SD大鼠24只，随机分为3组（每组8只）：①正常对照组，术中只分离肝周围韧带，不做肝门阻断及再灌注。②I/R组，进行45min的部分肝门阻断及60min的再灌注。③L-精氨酸（L—Arg）组，缺血前20min经阴茎背静脉注射L—Arg（300mg／kg），余同②组。实验结束后，取下腔静脉血2ml，并迅速切取缺血肝组织。检测血清丙氨酸转氨酶（ALT）、门冬氨酸转氨酶（AST）、乳酸脱氢酶（LDH）；测定肝组织中超氧化物歧化酶（SOD）、丙二醛（MDA）、黄嘌呤氧化酶（XOD）、一氧化氮（NO）和一氧化氯合成酶（NOS）等指标；观察光镜和电镜下肝组织学变化。结果与正常对照组相比，I／R组iNOS升高，NO降低；L-Arg组NO、eNOS均高于I／R组。2、3组比1组大鼠的肝组织病理损害重、肝功能差，L—Arg组病理损害较I／R组明显减轻、肝功能改善。结论NO对大鼠肝I／R损伤具有保护作用．不同亚型NOS的变化参与其中。     

强骨颗粒剂对去卵巢大鼠骨生化药理作用的探讨

目的 观察中药制剂强骨颗粒剂防治去卵巢所致骨质疏松大鼠的疗效,探讨其生化药理作用。方法 30只雌性Wistar大鼠,分为模型组（去卵巢）,假手术组（行假手术）、强骨颗粒（QGKL）组3组。观察了强骨颗粒对大鼠骨密度,血清骨钙素（S－BGP）,骨中水含量,骨灰重,子宫指数（子宫重量／体重）和肾脏指数（肾脏重量／体重）,红细胞和肾线粒体膜Ca^2 -ATPase活性、膜流动性的影响。结果 与去卵巢组比较,强骨颗粒可升高大鼠骨密度,抑制血清BGP升高,增加骨中水含量,增加肾脏指数、Ca^2 -ATPase活性和膜流动性。结论 强骨颗粒剂对去卵巢大鼠的骨质疏松有明显的防治作用,作用途径可能通过全身多方面的整体调节。     

Is Nitric Oxide a Mediator of the Effects of Low-Intensity Electrical Stimulation on Bone in Ovariectomized Rats?

Low-intensity electrical stimulation (LIES) may counteract the effects of ovariectomy (OVX) on nitric oxide synthase (NOS) expression, osteocyte viability, bone structure, and microarchitecture in rats (Lirani-Galvão et al., Calcif Tissue Int 84:502–509, 2009). The aim of the present study was to investigate if these effects of LIES could be mediated by NO. We analyzed the effects of NO blockage (by l-NAME) in the response to LIES on osteocyte viability, bone structure, and microarchitecture in OVX rats. Sixty rats (200–220 g) were divided into six groups: sham, sham-l-NAME (6 mg/kg/day), OVX, OVX-l-NAME, OVX-LIES, and OVX-LIES-l-NAME. After 12 weeks, rats were killed and tibiae collected for histomorphometric analysis and immunohistochemical detection of endothelial NOS (eNOS), inducible NOS (iNOS), and osteocyte apoptosis (caspase-3 and TUNEL). In the presence of l-NAME, LIES did not counteract the OVX-induced effects on bone volume and trabecular number (as on OVX-LIES). l-NAME blocked the stimulatory effects of LIES on iNOS and eNOS expression of OVX rats. Both l-NAME and LIES decreased osteocyte apoptosis. Our results showed that in OVX rats l-NAME partially blocks the effects of LIES on bone structure, turnover, and expression of iNOS and eNOS, suggesting that NO may be a mediator of some positive effects of LIES on bone.     

Overexpression of inducible nitric oxide synthase in gastric mucosa of rats with portal hypertension: correlation with gastric mucosal damage

BACKGROUND: An increased biosynthesis of nitric oxide (NO) has been implicated in the hyperdynamic circulation and development of collaterals of portal hypertension (PHT) because of its potent vasodilatory effects. NO is synthesized from L-arginine by three different isozymes of nitric oxide synthase (nNOS, iNOS and eNOS). Thus, the expression of inducible NOS (iNOS) might account for NO overproduction in PHT. However, in previous investigations, the role of iNOS in the pathogenesis of PHT gastropathy remained controversial. Our current study was in both molecular and protein levels to determine whether the expression of iNOS is responsible for PHT gastropathy. MATERIALS AND METHODS: PHT was induced experimentally by partial ligation of the portal vein. Fourteen days after partial ligation of the portal vein, the rats were randomly assigned to receive either vehicle or L-NAME (NOS inhibitor) at doses of 5 mg/kg/day, 10 mg/kg/day, or 25 mg/kg/day by gastric lavage twice a day for 1 week. Sham operated rats served as controls. Northern hybridization and in situ hybridization are used to compare the expression of gastric mucosa iNOS mRNA in the PHT rats and the controls. NO was measured by the Griess method after reduction of nitrate to nitrite with nitrate reductase. Immunohistochemical staining was carried out to detect the iNOS protein. In addition, the severity of gross gastric mucosal lesions was evaluated macroscopically by a gross ulcer index. RESULTS: The iNOS expression at both mRNA and protein was prominently increased in PHT rats, accompanied with the enhanced NO production. The gastric mucosa iNOS mRNA and serum NO levels were significantly decreased after L-NAME administration (P < 0.05). However, the markedly reduced gastric mucosal damage in PHT rats was observed only at high does of L-NAME (25 mg/kg/day) administration. CONCLUSION: PHT triggers overexpression of iNOS mRNA and proteins in rat gastric mucosa, but that this alone does not account for PHT gastropathy.     

Isoflavones with supplemental calcium provide greater protection against the loss of bone mass and strength after ovariectomy compared to isoflavones alone

Although hormone replacement therapy (HRT) and calcium (Ca) supplementation preserve bone mass more when combined, there is a growing concern over the safety of HRT that necessitates thorough investigation of effective, alternative treatments for bone loss. While plant-derived estrogen-like compounds such as isoflavones preserve bone, it is not known whether isoflavones and Ca supplementation attenuate losses in bone mass and strength to a greater extent when combined. This study compared the effects of an isoflavone extract + high Ca to isoflavone extract or high Ca alone on preservation of bone mineral density (BMD) and biomechanical strength in ovariectomized (ovx) rats. Rats were sham-operated (n = 10) or ovx (n = 40). Shams were fed a 0.2% Ca diet. Ovx rats were randomized to a 0.2% Ca diet alone (OVX) or with isoflavone extract (IE; 1.6 g/kg diet) or to a high Ca diet (Ca; 2.5%) alone or a high Ca diet with the isoflavone extract (IE + Ca) for 8 weeks. BMD of femur and lumbar spine were measured by dual-energy X-ray absorptiometry. The biomechanical strength of femurs and individual vertebra was measured by three-point bending and compression testing, respectively. The average food intake was lowest (P < 0.05) among sham and IE groups and greatest (P < 0.05) among the OVX group. Final body weight was lowest (P < 0.05) among shams and highest (P < 0.05) among the OVX group while IE + Ca were lighter (P < 0.05) than all ovx groups. Femur and vertebra BMD was greater (P < 0.05) among IE + Ca and sham rats compared to IE, Ca, or OVX rats. Although there were differences in femur BMD among groups, biomechanical properties at the femur midpoint did not differ among groups, possibly due to the lack of cortical bone loss at this site. Conversely, vertebra biomechanical strength was greater (P < 0.05) among IE + Ca and Ca alone groups compared to IE alone. Uterine weight was higher (P < 0.05) among shams than OVX and IE with no difference among shams, Ca, or IE + Ca rats, suggesting that the isoflavones did not have an uterotrophic effect. In conclusion, isoflavones combined with high Ca are more protective against the loss of femur and vertebra BMD than isoflavones or high Ca diet alone.     

Propofol reduces nitric oxide-induced apoptosis in testicular ischemia-reperfusion injury by downregulating the expression of inducible nitric oxide synthase

Background: The aim of the present study was to investigate the underlying mechanisms in the preventive effects of intravenous anesthetics on testicular ischemia–reperfusion injury.
Methods: Forty male Wistar Albino rats were randomly assigned to four groups of 10 rats each. Anesthesia was induced and maintained with thiopental in groups 1 and 2 and with propofol in groups 3 and 4. Groups 2 and 4 received left testicular ischemia (torsion) for 1 h and reperfusion (detorsion) for 24 h. Groups 1 and 3 (control groups) had no testicular torsion and detorsion. At 24 h of reperfusion, animals were killed and ipsilateral testes were removed for determination of tissue nitric oxide (NO) levels and immunohistochemical evaluation of endothelial nitric oxide synthase (eNOS), inducible NOS (iNOS), and apoptosis protease-activating factor 1 (APAF-1).
Results: Between groups 1 and 3, there were no differences in tissue NO levels and eNOS, iNOS, and APAF-1 expressions. iNOS and APAF-1 expressions were markedly increased in group 2, but these parameters were at the mild to moderate level in group 4 at 24 h of reperfusion. Also, elevated expression of iNOS was accompanied by a high NO production in group 2 compared with group 4. Although eNOS expressions were increased in both the groups (groups 2 and 4), there were no significant differences between these groups.
Conclusions: Propofol as an anesthetic agent may attenuate germ cell-specific apoptosis and decrease NO biosynthases through downregulation of iNOS expression in an animal model of testicular torsion and detorsion.     

去势成年雌性大鼠骨质疏松模型血清NO和N0S的水平及其意义

目的 测定大鼠骨质疏松模型血清中NO和NOS的水平,探讨骨质疏松症与NO和NOS浓度的关系。方法 6月龄成年雌性SD大鼠随机分成实验组和对照组,术前及术后均测量腰椎骨密度,术后分离血清,用改良镀铜镉还原法测定NO含量,用化学比色法测定NOS含量。结果 术前,两组大鼠骨密度差异无显著性,术后,实验组大鼠骨密度明显低于对照组骨密度,差异有显著性(P<0.05)。血清NO和NOS水平实验组明显低于对照组,差异有显著性(P<0.05),有统计学意义。结论NO和NOS在骨质疏松的病理生理过程中起重要作用。