红景天甙减轻大鼠酒精性肝损伤

目的:探讨红景天甙对大鼠酒精性肝损伤的作用及其可能机制。方法:将100只SD大鼠随机分为5组:对照组、模型组、联苯双酯滴丸组及红景天甙低剂量(20 mg/kg)和高剂量(40 mg/kg)组,除空白组给予生理盐水外,其余各组均给予56%乙醇灌胃,建立酒精性肝损伤大鼠动物模型,给药组同时予以相应药物灌胃,于末次给药后12 h采血,处死动物后取出肝脏,采用全自动生化仪测定血清甘油三酯(TG)、丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)水平,苏木素-伊红(HE)染色观察肝组织病理学改变,试剂盒测定肝组织中丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性,ELISA法测定各组大鼠血清中肿瘤坏死因子α(TNF-α)和核因子κB(NF-κB)水平,Western blot法和RT-PCR测定肝组织TNF-α和NF-κB的蛋白和mRNA表达。结果:与模型组比较,红景天甙高、低剂量组肝组织损伤程度明显减轻;红景天甙对酒精性肝损伤大鼠血清TG、ALT及AST水平均具有明显抑制作用(P0.05),并可降低肝组织MDA含量,增强肝组织SOD活性(P0.05);红景天甙各剂量组大鼠血清TNF-α和NF-κB含量降低(P0.05)。结论:红景天甙能够改善大鼠酒精性肝损伤病理变化,减轻肝组织炎症反应,增加抗氧化酶的活性,降低脂质过氧化,该作用可能与调节NF-κB介导的炎症反应有关。     

大豆异黄酮对非酒精性脂肪肝病大鼠的作用

目的探讨大豆异黄酮对高脂饮食诱导大鼠非酒精性脂肪肝病模型的干预作用。方法将50只SD大鼠随机分成5组:正常组,模型组,大豆异黄酮低剂量组(30mg/kg/d),大豆异黄酮中剂量组(100mg/kg/d),大豆异黄酮高剂量组(300mg/kg/d)。除正常组外,其余各组以高脂饮食诱导建立大鼠脂肪肝模型,测定大鼠血清中总胆固醇(TC)、甘油三酯(TG)含量,计算肝指数,对肝脏进行病理学检查,观察大豆异黄酮对该模型的影响。结果模型组大鼠血清中甘油三酯(TG)、胆固醇(TC)水平明显高于正常组(P<0.01);与模型组相比,SI高剂量组及中剂量组大鼠血清中TG、TC水平和肝指数水平均明显低于模型组(P<0.05),SI高剂量组及中剂量组大鼠肝组织的病理损伤明显改善。结论大豆异黄酮对高脂饮食诱导的大鼠脂肪肝有明显的干预作用。     

苦瓜对实验性大鼠肝纤维化的干预作用及可能机制

目的: 探讨苦瓜(BM)对四氯化碳(CCl₄)诱导大鼠肝纤维化的干预作用及相关机制。方法: 随机将32只雄性健康Wistar大鼠分为4组:对照组(C组);模型组(CCl₄,M组);BM低剂量组(BM 100g/kg饲料+CCl₄,BM-L组)、BM高剂量组(BM 200g/kg饲料+CCl₄,BM-H组)。饲养中除C组外的各组大鼠均皮下注射50%CCl₄-橄榄油溶液2 mL/kg,2次/周,共8周,诱导肝纤维化动物模型。8周后处死大鼠,留取大鼠肝脏和血清。计算肝体指数;测定血清丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;测定肝匀浆总蛋白(TP)和白蛋白(Alb)含量、谷胱甘肽过氧化物酶(GSH-Px)活性、羟脯氨酸(HYP)含量和单胺氧化酶(MAO)活性;胶原纤维染色观察大鼠肝组织变性与胶原沉积病理改变。结果: 与M组比较,摄入BM后的各剂量组大鼠肝体指数显著降低(P<0.01);血清MDA含量及肝匀浆HYP含量和MAO活性均明显降低(P<0.01),而血清SOD活性、肝组织TP和Alb含量、GSH-Px活性明显增强(P<0.01)。与正常大鼠相比,模型大鼠肝脏有明显胶原沉积与肝纤维化,伴有不同程度的肝细胞炎性损伤坏死;BM组明显减轻模型大鼠肝组织损伤坏死与胶原沉积等病理变化,以高剂量组更明显。结论: BM具有抗CCl₄诱导大鼠肝纤维化作用,其机制可能与其抗脂质过氧化、降低肝HYP含量及MAO活性的作用有关。     

丹参对内毒素性肝损伤及肝脏微循环障碍大鼠的防护机制研究

目的:探讨丹参对内毒素性肝损伤及肝脏微循环障碍大鼠的防护机制。方法:将70只大鼠随机分为正常对照组,内毒素注射后6h、12h、24h组和相同时相的丹参防护组,共7组。丹参防护组于制模前3天经大鼠腹腔注射丹参注射液,剂量为40mg/kg,连续3天,除正常对照组0h处死,肝组织取材外,其它各组均于内毒素注射后6h、12h、24h分别处死,取肝脏组织匀浆,制备肝细胞线粒体悬液,检测肝细胞线粒体超氧化物歧化酶(SOD)、丙二醛(MDA)、三磷酸腺苷(ATP),肝组织肿瘤坏死因子-α(TNF-α)及内皮素-1(ET-1)。结果:丹参防护组与相应时相内毒素组比较,SOD、ATP活性显著升高(P<0.01),MDA、TNF-α、ET-1活性显著降低(P<0.01)。结论:丹参能明显抑制肝细胞脂质过氧化反应,从而使肝细胞变性坏死减轻,改善生物转化功能,保护肝细胞,改善肝脏局部血液循环。     

胸腺在大鼠肝脏自由基代谢中的作用

本文以成年去胸腺大鼠为模型,旨在观察胸腺对肝脏自由基代谢的影响。实验结果表明,雌性去胸腺大鼠和雌、雄性老年大鼠肝匀浆及肝微粒体过氧化脂质增多,肝匀浆超氧化物歧化酶活力和还原型谷胱甘肽含量降低,但雄性去胸腺大鼠上述指标与对照组相比无明显变化。     

异丙肾上腺素ISP致心肌微血管阻塞的机理探讨

本实验通过对血浆凝固性的动态变化和自由基系统有关指标的变化的监测以及心肌组织病理学观察发现,大鼠皮下注射大剂量异丙肾上腺素(ISP)(85mg/kg)后早期(4h以前)即有明显的血浆高凝状态、内源性凝血系统激活和心肌微血管内血栓形成,且心肌缺血损伤程度与血浆凝固性紊乱程度之间呈正直线相关;心、肝、肾和脑以及血清MDA含量显著增加(P<0.01),心肌的SOD和GSH—Px活性均显著增高。提示ISP引起的膜脂质过氧化、血浆高凝状态以及由此而引发的血管内皮受损和微血栓形成是ISP致心肌微血管阻塞的重要机理。     

羟基红花黄色素A对肝纤维化大鼠血清学指标及脂质过氧化的影响

目的观察羟基红花黄色素A(HYSA)对四氯化碳(CCl4)诱导的肝纤维化(HF)大鼠血清学指标及脂质过氧化的影响。方法清洁级雄性SD大鼠60只,体重(180±30)g,随机分为A、B、C、D、E组,A组(正常对照组)、B组(HF模型组)、C组(红花组)、D组(HYSA组)、E(秋水仙碱组),除A组外,其余各组采用CCl4灌胃,诱导大鼠肝纤维化模型;造模第2周起,腹腔注射给予相应药物,8w后处死大鼠取血清及肝组织标本,光景下观察肝组织结构变化及肝纤维化程度,放射免疫技术检测测定血清中ALT、AST、ALB含量,分光光度计检测肝组织匀浆中SOD和MDA的含量。结果与B组比较,C、D、E组大鼠血清中ALT、AST活性显著降低,ALB含量显著升高,肝细胞变性、坏死明显减少,肝组织纤维化程度明显减轻,肝组织MDA含量显著降低,SOD活性显著升高;与C组比较,D组的肝纤维化程度显著减轻,两者比较有统计学意义(P<0.05)。结论 HYSA作为红花抗肝纤维化的主要有效作用成分,能够保护肝组织,减轻肝细胞水肿程度,减轻其纤维化程度,并能促进损伤肝组织的修复,且其抗肝纤维化作用机制可能与其抗脂质过氧化作用有关。     

MnTBAP对脊髓损伤大鼠脂质过氧化和运动功能的影响

目的观察脊髓损伤(SCI)后锰卟啉(MnTBAP)对损伤早期脂质过氧化反应、活性氧水平和伤后4W内运动功能的影响,探讨MnTBAP对脊髓继发性损伤的保护作用。方法用钳夹法制备大鼠SCI模型,分为假手术组、损伤组、MnTBAP治疗组和甲基强的松龙(MP)治疗组。损伤组术后立即腹腔注射生理盐水,MnTBAP组伤后立即腹腔注射MnTBAP(10mg/kg体重),MP组伤后立即腹腔注射MP(100mg/kg)。经1、6、12、24h,取SCI段标本,用于测定损伤段脊髓超氧化物歧化酶(SOD)、脂质过氧化产物丙二醛(MDA)和活性氧水平(ROS),经1、7、14、21、28d,进行斜板试验,评价运动功能。结果与假手术组相比,损伤组伤段脊髓组织SOD显著减少(均<0.01),MDA和ROS显著增加(均<0.01);与损伤组相比,MnTBAP治疗组伤段脊髓组织SOD水平显著增加(均<0.01),相反,MDA和ROS水平显著减少(均<0.01),其作用和MP相当;斜板试验结果观察,除1d组外,MnTBAP治疗组斜板角度与损伤组相比明显增加(均<0.01)。结论 MnTBAP有效抑制SCI早期受损脊髓脂质过氧化反应和活性氧水平,改善SCI大鼠运动功能,对继发性SCI具有保护作用。     

罗哌卡因调节SIRT1/AMPK通路对妊娠期糖尿病大鼠的保护作用

目的 探讨罗哌卡因调节沉默信息调节因子2相关酶1(SIRT1)/腺苷酸活化蛋白激酶（AMPK）信号通路对妊娠期糖尿病（GDM）大鼠的保护作用。方法 雌性大鼠经高脂高糖喂养8周后与雄性大鼠合笼获得孕鼠,妊娠第6 d腹腔注射STZ制备GDM大鼠模型。将造模成功的大鼠随机分为模型组和罗哌卡因低剂量组（1 mg/kg）、高剂量组（2.0 mg/kg）,罗哌卡因高剂量（2.0 mg/kg）+EX-527(1 mg/kg)组,另设对照组,每组15只。全自动生化分析仪检测谷丙转氨酶（GPT）、谷草转氨酶（GOT）和碱性磷酸酶（ALP）活性,以及大鼠血清TC、TG、LDL-C、HDL-C含量;HE染色观察肝组织病理变化;ELISA法检测血清TNF-α、IL-6和IL-1β水平;商品化试剂盒检测肝脏组织MDA、SOD、GSH水平;Western blot检测肝组织Bcl-2、Bax、SIRT1、AMPK蛋白水平。结果 对照组肝组织细胞形态结构正常;与对照组相比,模型组大鼠肝组织有明显脂肪空泡和炎症细胞浸润,血清TG、TC、LDL-C水平、GPT、GOT、ALP水平、TNF-α、IL-6和IL-1β水平、...     

胡黄连甙元对大鼠两次打击损伤的保护作用

目的评价在失血性休克大鼠复苏液中伍用胡黄连甙元apocynin,对随后发生的脓毒症造成多器官组织损伤的保护效果.方法采用大鼠"两次打击”损伤模型.大鼠随机分为七组正常对照组,内毒素(LPS)组(ivLPS150μg/kg),失血性休克组(BP40mmHg,45min),两次打击组(失血性休克40mmHg,45min,ivLPS150μg/kg)及两次打击+apocynin(2.5,5,10mg/kg)组.评价指标采用(1)大鼠存活时间及存活率;(2)在ivLPS(或NS)后不同时相点(0.5,1,2,4,6h)取大鼠血清及肺、肝组织(3h、6h),检测血清丙二醛(MDA)含量及组织髓过氧化物酶(MPO)活力及MDA含量.结果(1)两次打击组大鼠较正常对照组,LPS组及失血性休克组大鼠存活时间缩短,8h,1d,3d存活率显著降低;肺、肝组织(3h,6h)MPO活力显著升高,肺组织(3h,6h)MDA含量显著增多,ivLPS后不同时相点血清MDA含量显著升高;提示病理模型有效.(2)在休克复苏液中伍用apocynin(2.5,5,10mg/kg),可显著延长两次打击大鼠存活时间,提高存活率,尤中剂量组(5mg/kg)效果较理想.(3)Apocynin(5mg/kg)可显著降低两次打击组大鼠肺、肝组织升高的MPO活力(尤6h),显著降低肺组织MDA含量,显著降低ivLPS4h,6h后的血清MDA含量.结论(1)胡黄连甙元apocynin具有较理想的两次打击损伤保护作用,显著延长大鼠存活时间.(2)胡黄连甙元apocynin的抗两次打击损伤作用与降低组织脂质过氧化损伤,抑制中性粒细胞在重要脏器(肺、肝)的趋化、粘附、干预中性粒细胞功能有关.     

Prostacyclin release from endothelial cells, induced by defibrotide treatment, favours the function of grafted rat hearts and kidneys.

Defibrotide, a single-stranded DNA fraction obtained from mammalian lungs and able to increase prostacyclin production by endothelial cells, has been shown to be efficient in protecting rat organs (heart, kidney and liver) from ischaemic damage. We studied the efficacy of the drug in preserving the function of rat heart and kidney submitted to isotransplantation. Defibrotide was administered to donor Wistar rats at the dose of 32 mg/kg in 1.5 ml of saline. Heart and kidney were isolated and cold-preserved in buffered phosphate medium and continuously infused with defibrotide (32 mg/h) through the innominate or renal artery. Recipient Wistar rats were treated with defibrotide before and after transplantation at the dose of 32 mg/kg/day. Controls were treated with the vehicle of the drug. The function of isografted organs was evaluated at 12 and 24 h and at 2, 4 and 7 days from grafting. Heart function was evaluated by studying creatinine phosphokinase (CPK) and lactic dehydrogenase (LDH) activities of myocardial tissue. Renal function was evaluated by studying serum creatinine and urea levels of kidney-grafted rats. CPK and LDH activities were found to be significantly higher in defibrotide-treated rats than in controls. Creatinine and urea levels remained significantly lower in defibrotide-treated rats than in the controls. The results of the present work indicate that defibrotide treatment is useful to maintain the functionality of grafted hearts and kidneys.     

全反式维甲酸对生长发育期大鼠实质器官的损伤

目的 探讨体内过量全反式维甲酸（ATRA）对生长发育期SD大鼠的脑、心、肺、肝、肾和脾的影响。方法 以48只3周雄性SD大鼠为实验对象,随机分为对照组和3个实验组,ATRA剂量分别为40、60、80 mg/(kg·d),每组12只,进行连续10 d ATRA灌胃处理,记录SD大鼠每日体重,于灌胃第10天解剖称量各器官的重量以及计算脏器指数,然后对各器官进行HE染色。结果 ATRA灌胃后,与对照组比较,40 mg/(kg·d) ATRA组肾指数升高,体重变化差异无统计学意义;60 mg/(kg·d) ATRA组体重降低,心、肾指数升高,脾脏重量降低;80 mg/(kg·d)ATRA组体重明显降低,脑、心、肾指数升高,脑、脾重量降低;HE染色显示,与对照组比较,ATRA处理组的肺泡壁增厚,肾小管上皮细胞有空泡样改变,脾脏红髓出现较多巨噬细胞,而大脑、肝脏、心肌无明显组织学变化。结论 体内过量全反式维甲酸能够对生长发育期SD大鼠的肺、肾和脾有一定的损伤作用。     

金丝桃苷对CCl4诱导大鼠急性肝损伤抗氧化应激研究

目的研究金丝桃苷（Hyp）对四氯化碳（CCI。）诱导大鼠急性肝损伤的治疗作用。方法采用大鼠CCl4急性肝损伤模型,观察Hyp对急性肝损伤大鼠肝脏组织病理学改变的影响;检测肝组织匀浆中超氧化物歧化酶（T-SOD）、谷胱甘肽（GSH）的活性及丙二醛（MDA）含量变化。结果CCl4模型组大鼠肝组织HE染色病理检测结果见明显炎症变性死及纤维组织增生现象;Hyp高剂量60mg／kg、中剂量30mg／kg治疗组的肝组织病理改变明显改善;Hyp治疗组肝组织中T—SOD、GSH活性明显升高,MDA含量明显降低,并存在量效关系。结论Hyp对CCl4引起的大鼠急性肝损伤有较好的治疗作用,其机制可能与其抗氧化活性有关。     

Bioavailability, tissue distribution and hypoglycaemic effect of vanadium in magnesium-deficient rats

Vanadium is an element whose role as a micronutrient and hypoglycaemic drug has yet to be fully clarified. The present study was undertaken to investigate the bioavailability and tissue distribution of vanadium and its interactions with magnesium in healthy and in magnesium-deficient rats, in order to determine its role as a micronutrient and antidiabetic agent. Four groups were used: control (456.4 mg magnesium and 0.06 mg vanadium/kg food); control treated with 1mg vanadium/day; magnesium-deficient (164.4 mg magnesium/kg food and 0.06 mg vanadium/kg food); and magnesium-deficient treated with 1 mg vanadium/day. The vanadium was supplied in the drinking water as bis(maltolato)oxovanadium (IV). The experiment had a duration of five weeks. We measured vanadium and magnesium in excreta, serum, skeletal muscle, kidney, liver, adipose tissue and femur. Fasting glucose, insulin and total antioxidant status (TAS) in serum were studied. The vanadium treatment applied to the control rats reduced the absorption, retention, serum level and femur content of magnesium. Magnesium deficiency increased the retention and serum level of vanadium, the content of vanadium in the kidney, liver and femur (organs where magnesium had been depleted), serum glycaemia and insulin, and reduced TAS. V treatment given to magnesium-deficient rats corrected magnesium content in muscle, kidney and liver and levels of serum glucose, insulin and TAS. In conclusion, our results show interactions between magnesium and vanadium in the digestive and renal systems. Treatment with vanadium to magnesium-deficient rats corrected many of the alterations that had been generated by the magnesium deficiency.     

Fourteen-week toxicity study of green tea extract in rats and mice

The toxicity of green tea extract (GTE) was evaluated in 14-week gavage studies in male and female F344/NTac rats and B6C3F1 mice at doses up to 1,000 mg/kg. In the rats, no treatment-related mortality was noted. In the mice, treatment-related mortality occurred in male and female mice in the 1,000 mg/kg dose groups. The cause of early deaths was likely related to liver necrosis. Treatment-related histopathological changes were seen in both species in the liver, nose, mesenteric lymph nodes, and thymus. In addition, in mice, changes were seen in the Peyer's patches, spleen, and mandibular lymph nodes. The no adverse effect level (NOAEL) for the liver in both species was 500 mg/kg. In the nose of rats, the NOAEL in males was 62.5 mg/kg, and in females no NOAEL was found. No NOAEL was found in the nose of female or male mice. The changes in the liver and nose were considered primary toxic effects of GTE, while the changes in other organs were considered to be secondary effects. The nose and liver are organs with high metabolic enzyme activity. The increased susceptibility of the nose and liver suggests a role for GTE metabolites in toxicity induction.     

Burn-Induced Multiple Organ Injury and Protective Effect of Lutein in Rats

Thermal injury may lead to multiple organ dysfunction through release of proinflammatory mediators and reactive oxygen radicals. This study investigated the effects of thermal injury on remote organs of rats and the possible protective effect of lutein. Thermal trauma was induced in the back of rats by exposing them to 90 °C bath for 10 s. Rats were sacrificed 48 h after burn, and blood samples were collected to monitor liver and kidney functions. Tissue samples from liver, kidneys, and lungs were taken for studying oxidative stress parameters, gene expressions of TNF-α and Casp-3, besides histopathological examination. Skin scald injury caused significant elevations of liver and kidney function biomarkers in the serum. In tissue samples, increments of MDA, GPx, and 8-OHdG were recorded while GSH level and the activities of CAT and SOD were suppressed. The expressions of TNF-α and caspase-3 mRNA were increased, and histopathological results revealed remote organ injury. Oral administration of lutein (250 mg/kg) resulted in amelioration of the biochemical and molecular changes induced by burn as well as the histopathological alterations. According to the findings of the present study, lutein possesses anti-oxidant, anti-inflammatory, and anti-apoptotic effects that protect against burn-induced damage in remote organs.     

Defibrotide, a stimulator of prostacyclin (PGI2) production, prevents the effects of ischaemic damage

Defibrotide, a polydeoxyribonucleotide obtained from mammalian lungs, has been demonstrated to exert profibrinolytic and antithrombotic activity through stimulation of vascular prostacyclin (PGI2) production. We studied the effect of defibrotide administration in protecting liver and heart from ischaemic and postischaemic reperfusion damage. Defibrotide was administered as an i.v. bolus (30 mg/kg) at the beginning of liver ischaemia and at the same dose continuously during 60 min of postischaemic reperfusion. ATP levels were significantly improved in livers of defibrotide-treated rats as compared to those obtained in livers of rats treated with vehicle of the drug. Intrahepatic cytoplasmic and mitochondrial NAD+/NADH ratios were higher in defibrotide-treated than in vehicle-treated animals. The hearts, isolated from rats according to the transplantation procedure, were subjected to different times of warm + cold ischaemia. During ischaemia, the hearts were perfused continuously with 60 mg/kg of defibrotide or vehicle of the drug. The loss of creatine phosphokinase and lactate dehydrogenase activities due to an increased ischaemia time was limited in defibrotide-perfused hearts. Intracardiac ATP and ADP levels were significantly higher in defibrotide-treated organs than in controls. Our results demonstrate the efficacy of defibrotide in protecting liver and heart from ischaemia.     

Influence of zinc supplementation on histopathological changes in the stomach,liver, kidney,brain, pancreas and spleen during subchronic exposure of Wistar rats to glyphosate

A subchronic toxicity study was carried out to determine the glyphosate-induced histopathological changes in the stomach, liver, kidney, brain, pancreas and spleen of rats and the attendant ameliorative effect when pretreated with zinc at the dose rate of 50 mg/kg body weight. The rats were exposed to two doses of the glyphosate (375 and 14.4 mg/kg body weight) for the period of 8 weeks which was the duration of the study, and some groups were exposed to the glyphosate after pretreatment with zinc. The histopathological changes recorded during the study were only in the rats exposed to the glyphosate at the dose rate of 375 mg/kg body weight except the vacuolation encountered in the brains and haemosiderosis in the spleens of rats exposed to zinc alone. Degenerated mucosal epithelial cells which involved the muscularis mucosa and the glands in the stomachs of rats were seen microscopically. Hepatic cells degeneration especially at the portal areas of the livers of rats was observed. The histopathological examination of the kidneys showed glomerular degeneration, mononuclear cells infiltration into the interstices of the tubules and tubular necrosis. The conspicuous changes seen in the brains were neuronal degeneration. Pancreatic acinar cells were degenerated while the spleen of the rats showed depopulated splenic cells in both the red and the white pulps. It was concluded that zinc supplementation in rats prior to glyphosate exposure ameliorated the histopathological changes observed in the stomach, liver, kidney, brain, pancreas and spleen with no observable alteration in the histoarchitecture in the organs of the zinc-supplemented rats.     

海星甾烯AST对异丙肾上腺素致大鼠心肌缺血的保护作用

目的观察从海星提取并经结构修饰而获得的新化合物丁二酸二-3β-羟基雄5烯-17酮酯(AST)对异丙肾上腺素致大鼠心肌缺血的保护作用。方法大鼠随机分5组:对照组口服0.5%CMC,AST组分低、中、高3剂量组和硝苯地平组。首次给药后大鼠皮下注射异丙肾上腺素致心肌缺血模型,计算各时间段∑ST的mv数均值作为心肌损伤程度的指标;测量首次注射异丙肾上腺素72 h血清和心肌匀浆中的肌酸激酶、乳酸脱氢酶和丙二醛的含量。结果AST能降低皮下注射异丙肾上腺素引起的ST段的异常升高,降低丙二醛的含量,防止肌酸激酶和乳酸脱氢酶从心肌细胞向血液中的漏出。结论 AST能有效保护异丙肾上腺素致大鼠心肌缺血损伤。