牛磺酸对百草枯中毒大鼠肾损伤的作用及机制研究

目的:探讨不同剂量牛磺酸对百草枯中毒大鼠肾脏氧化应激和炎症反应的影响。方法:选取48只雄性SD大鼠随机分为阴性对照组、百草枯染毒组、百草枯染毒+小剂量牛磺酸组和百草枯染毒+大剂量牛磺酸组。采用生化检测仪检测大鼠血清肌酐及尿素氮水平;比色法检测血标本中丙二醛(malondialdehyde,MDA)和超氧化物歧化酶(superoxide dismutase,SOD)水平评估氧化应激状态;另以ELISA法检测血标本中IL-6及细胞间黏附分子1(ICAM-1)水平评估炎症反应;DHE荧光探针检测肾脏活性氧簇(reactive oxygen species,ROS)水平;Western blot法检测大鼠肾脏标本丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)中p-P38 MAPK、p-JNK和pERK1/2的蛋白水平;并以real-time PCR法检测大鼠肾脏内TNF-α、TGF-β1及IL-6的mRNA水平。结果:百草枯中毒大鼠血清肌酐及尿素氮增高,牛磺酸干预后降低了中毒大鼠的肌酐及尿素氮水平,且大剂量牛磺酸组的肌酐及尿素氮水平更低。牛磺酸的干预不仅明显减轻了肾脏组织的氧化应激与炎症反应,同时也降低了百草枯中毒大鼠肾脏的MAPK活性。结论:牛磺酸干预能减轻百草枯中毒大鼠的肾损伤,其作用机制可能与下调了肾脏MAPK活性、减轻了肾脏氧化应激及炎症反应有关。     

Pink-1在百草枯中毒大鼠肾损伤中的表达及意义

目的探讨Pink-1在百草枯(PQ)中毒大鼠肾损伤中的表达及意义。方法35只健康SD大鼠随机分为7组,每组5只,分别为对照组(NC组)、PQ染毒3h、6h、9h、12h、24h、48h组。用HE染色方法分别观察各组大鼠肾组织病理学变化,同时采用IHC、Western blot方法观察Pink-1蛋白表达情况。结果对照组肾脏组织结构清晰,染毒组结构清晰度下降。染毒3h即可见充血、水肿等病理变化,随时间延长而加重,肾小球亦可受累。与对照组相比,PQ组染毒9h、12h、24h、48h的Pink-1蛋白表达量上升(P0.05)。结论Pink-1蛋白可能参与百草枯中毒肾损伤的病理机制。     

Protective effect of melatonin against maternal deprivation-induced acute hippocampal damage in infant rats

It is known that maternal deprivation induces hippocampal damage in the developing brains. In the present study, we examined the effects of melatonin on maternal deprivation-induced hippocampal damage both during and after stress-hyporesponsive period (SHRP). Hippocampal damage was examined by cresyl violet staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The results showed that a single episode of maternal deprivation for 24 h at post-SHRP induced neuronal loss in hippocampus regions of the brain in the infant rats, while it did not influence hippocampal neurons in SHRP. Melatonin prevented maternal deprivation-induced hippocampal damage in the infant rats at post-SHRP. These results suggest that melatonin is a potentially beneficial agent to improve the neurobehavioral outcomes of maternal deprivation in later developmental period.     

Pulmonary ultrastructure of the late aspects of human paraquat poisoning.

The pulmonary ultrastructure of the late aspects of a case of human paraquat poisoning is investigated and compared with normal human pulmonary ultrastructure. Alveoli in the paraquat patient are numerically reduced in comparison to the control. They are filled with edematous proteinaceous plasma-like fluid containing erythrocytes, macrophages, leukocytes, fibroblast-like cells, platelets, and fibrin. These alveoli are lined by granular pneumocytes. Interstitial areas in the paraquat patient are greatly expanded and there are no alveolar septums. Interstitial areas contain proteinaceous plasma-like material, collagen, fibrin, platelets, mature fibroblasts, plasma cells, many leukocytes, numerous erythrocytes, and capillaries. Capillary permeability seems to be enhanced in the paraquat patient either by vesicles forming transendothelial channels or pores or by disruption of endothelial cells.     

Protective effect of melatonin on beta-cell damage in streptozotocin-induced diabetes in rats

The aim of the present study was the evaluation of possible protective effects of melatonin against beta-cell damage in streptozotocin-induced diabetes in rats. Malondialdehyde levels and glutathione peroxidase activity were measured in pancreatic homogenates. Pancreatic beta-cells were examined by immunohistochemical methods. Streptozotocin was injected intraperitoneally at a single dose of 60 mg/kg for induction of diabetes. Melatonin (200 microg/kg/day, ip) was injected for 3 days prior to administration of streptozotocin; these injections were continued until the end of the study (4 weeks). Streptozotocin induced a significant increase in malondialdehyde levels (p < 0.01) and a significant decrease in glutathione peroxidase activity (p < 0.05) in pancreatic tissue. Degeneration of islet cells and weak immunohistochemical staining of insulin was observed in diabetic rats. Treatment of diabetic rats with melatonin markedly reduced malondialdehyde production (p < 0.05) and increased glutathione peroxidase activity (p < 0.01) without affecting hyperglycemia. Increased staining of insulin and preservation of islet cells were apparent in the melatonin-treated diabetic rats. These data suggest that melatonin treatment has a therapeutic effect in diabetes by reduction of oxidative stress and preservation of pancreatic beta-cell integrity.     

脂氧素A4对横纹肌溶解所致急性肾损伤大鼠肾的保护作用

目的:探讨脂氧素A4(LXA4)是否能减轻横纹肌溶解所致急性肾损伤(AKI)大鼠肾损害程度并探讨其机制。方法:将SD大鼠随机分成健康对照组、AKI组和LXA4干预组(造AKI模型同时腹腔注射LXA4);采用大鼠双侧后腿注射甘油建立横纹肌溶解所致AKI动物模型。常规生化方法检测血肌酐、血尿素氮的水平,HE染色观察肾脏组织学改变,ELISA法检测血清TNF-α及IL-6水平,比色法检测肾组织MPO的活性,Western blot法检测肾组织NF-κB的蛋白表达。结果:与AKI组相比,LXA4干预组的血尿素氮及肌酐水平明显下降(P<0.05),肾脏病理损害明显改善;血清TNF-α及IL-6水平表达明显下降(P<0.05),肾组织MPO的活性及NF-κB表达明显下降(P<0.05)。结论:LXA4对横纹肌溶解所致急性肾损伤有明显的保护作用,可能与LXA4降低肾组织NF-κB活化,减少炎症因子的产生和炎症细胞的浸润有关。     

高氧液对大鼠急性一氧化碳中毒脑损伤保护作用的研究

目的:探讨不同剂量高氧液(hyperoxygenated solution,HOS)对急性CO中毒脑损伤的保护作用,为临床应用提供实验依据。方法:将30只SD大鼠随机分为5组,每组6只。正常组(N组)、中毒组(C组)和中毒治疗组(H组),H组再根据输注HOS剂量不同分为,HOS 10 ml/kg(H10组)、15 ml/kg(H15组)和20 ml/kg(H20组)。C组与H组大鼠经腹腔注入CO 120 ml/kg建立中毒模型,N组给予等量空气。各组大鼠分别在输注不同剂量的液体后即刻取血0.5 ml行血气检测,1 d抽取血3 ml进行神经元特异性敏感生化指标测定。实验结束后,所有动物均在麻醉状态下切取部分脑组织制作病理切片行病理学观察。结果:CO 120 ml/kg腹腔注射1.5 h能引起严重的低氧血症。中毒后1 d神经元特异性烯醇化酶、S-100β蛋白明显升高(P0.01)。中毒后24 h脑细胞出现明显水肿、间质增宽。中毒治疗组在静脉输注不同剂量的HOS后,动脉血氧分压(mm Hg)由43.04±4.13分别上升到69.56±3.41、77.11±2.49和81.65±3.85,脑组织病理学改变明显减轻,其中H20组降低最明显,具有显著的剂量依赖性。结论:HOS能明显提高CO中毒大鼠的Pa O2和动脉血氧饱和度,降低神经元特异性敏感指标的含量,对一氧化碳中毒脑损伤具有很好的保护作用,并具有剂量依赖关系。     

Protective effect of melatonin against zonisamide-induced reproductive disorders in male rats

Introduction

Zonisamide (ZNS) is a modern antiepileptic drug (AED) that is distinguished from other AEDs by its unique structure and broad mechanistic profile. The pineal hormone melatonin is involved in the regulation of reproductive function, including the timing of the luteinizing hormone (LH) surge. The aim of the present work was to study the protective effect of melatonin against the potential suppression impact of ZNS on reproductive activity.

Material and methods

Ninety adult albino male rats were allocated to several groups treated with melatonin (10 mg/kg BW), ZNS (10, 20 and 50 mg/kg BW) and 10 mg/kg of melatonin plus ZNS (10, 20 or 50 mg/kg BW, respectively). Reproductive hormones (testosterone, LH and follicle-stimulating hormone (FSH)) levels were measured in animal serum. Sperm abnormalities and DNA fragmentation in testis tissues as well as expression alteration of several reproductive-related genes were analyzed.

Results

The results revealed that ZNS decreased the levels of serum free testosterone, LH, and FSH and expression of their encoding genes in male rats. In addition, ZNS treatment increased the sperm abnormalities and DNA fragmentation and inducible nitric oxide synthase (iNOS) in testis tissues as well as GABA level in liver tissues. However, melatonin supplementation inhibited the negative symptoms of ZNS in which it increased the levels of reproductive hormones and expression of their encoding genes in the ZNS-treated rats. Moreover, melatonin decreased the sperm abnormalities, DNA fragmentation, iNOS activity and GABA level in ZNS-treated rats.

Conclusions

The data obtained in this study suggest that melatonin administration confers protection against toxicity inflicted by ZNS, and support the contention that melatonin protection is achieved by its ability as a scavenger for free radicals generated by ZNS.     

Protective effect of decorin on acute ischaemia-reperfusion injury in the rat kidney

Introduction

Transforming growth factor-β1 (TGF-β1) has a crucial role in collagen synthesis and fibrosis. TGF-β1 can be antagonized and/or reduced by the action of certain agents. We propose to identify the role of decorin in treatment of tubular and interstitial fibrosis and in the inhibition of TGF-β1 in an acute ischaemic kidney.

Material and methods

We grouped 34 female Sprague Dawley type rats into 3 groups as 9 sham, 9 ischaemia-reperfusion (I/R) and 16 I/R + decorin respectively. The rats in the I/R + decorin group had decorin administered intraperitoneally at the dose of 0.1 mg/kg for 9 days after reperfusion. After 9 days, all the rats in the 3 groups were unilaterally nephrectomized. The TGF-β1 level was measured immunohistochemically in the nephrectomized material.

Results

The TGF-β1 level was lower in the I/R + decorin group. Evaluation of apoptotic activity level by caspase staining showed a statistically significant difference between the 3 groups. The number of caspase stained cells was lower in the I/R + decorin group. The amount of collagen in interstitial tissue was higher in the I/R group than in the I/R + decorin group, but this difference was not statistically significant.

Conclusions

We found that the TGF-β1 level – the so-called initiator of fibrotic activity – and apoptotic activity were low in the I/R + decorin group. Additional studies must be performed to understand the role of decorin in inhibition of TGF-β1 and to assess decorin’s routine use in acute renal ischaemia.     

褪黑素对烟雾吸入所致大鼠急性肺损伤的保护作用

目的通过建立褪黑素干预大鼠烟雾吸入性损伤模型,探讨褪黑素对急性肺损伤的保护作用。方法成年清洁级雄性SD大鼠72只随机分为空白组、损伤组和褪黑素组。空白组不做任何处理,损伤组于吸入性损伤处理后腹腔注射1%乙醇生理盐水（10ml/kg）,褪黑素组于吸入性损伤处理后腹腔注射褪黑素（10mg/kg,1次/8h）。三组大鼠分别在3h、12h、24h三个时相腹主动脉取血2ml后处死,动脉血离心后检测肿瘤坏死因子α（TNF-α）、白细胞介素6（IL-6）含量和白细胞介素10（IL-10）。肺组织匀浆测超氧化物歧化酶（SOD）、丙二醛（MDA）、髓过氧化物酶（MPO）的含量。取右下肺组织作病理切片,光镜下观察肺组织病理情况。结果光镜下见空白组大鼠肺泡腔结构完整,壁光滑;损伤组肺泡壁增厚,肺间质炎症细胞浸润;褪黑素组肺组织较损伤组病理表现有所减轻。褪黑素组各时相点血清TNF-α和IL-6含量高于空白组（P〈0.05）,低于损伤组（P〈0.05）。损伤组各时相点IL-10含量与空白组相比无统计学差异（P〉0.05）,而褪黑素组IL-10含量与空白组、损伤组相比均升高（P〈0.05）。褪黑素组各时相点肺组织SOD含量均高于损伤组（P〈0.05）,低于空白组（P〈0.05）。褪黑素组各时相肺组织MDA和MPO含量均高于空白组（P〈0.05）,低于损伤组（P〈0.05）。结论褪黑素可以减轻炎症及氧化应激,对烟雾吸入性损伤所致急性肺损伤发挥一定的保护作用。     

黄芪甲苷对糖尿病肾病大鼠肾脏的保护作用及其机制

 目的:观察黄芪甲苷 (AS-IV)对糖尿病肾病(DN)肾脏的保护作用及其机制。方法:38只清洁级雄性SD 大鼠分成正常组（10只）、模型组（14只）和AS-IV 干预组（14只）,用链脲佐菌素造模,成功后1 周开始治疗,期间每 4周动态观测血糖及尿微量白蛋白,治疗12周后处死大鼠取材及采血,取肾皮质行 HE 和Masson染色观察,并检测β 1整合素、整合素连接激酶(ILK)和α-actinin-4的蛋白表达水平。结果:干预8周末AS-IV 组血糖水平较模型组明显降低（P<0.01）。干预12周末AS-IV 组与模型组相比,尿微量白蛋白明显下降（P<001）,并使因造模引起的β 1整合素、ILK 和α-actinin-4 表达水平的变化产生逆变（P<0.05）。与正常组比较,模型组的β 1整合素、ILK 和α-actinin-4 表达水平均有明显差异（P<0.05）。结论:AS-IV 对DN 肾脏有明显保护作用,能降低血糖和尿白蛋白排泄量,改善足细胞黏附功能,从而延缓DN 的进展。     

Cyanide toxicity of sodium nitroprusside in therapeutic use with and without sodium thiosulphate

Summary Sodium nitroprusside (SNP) as a monoinfusion was administered to 51 patients for periods of a few hours. A further group of 19 patients received SNP for periods of several days as a combination solution of SNP mixed with sodium thiosulphate. The concentrations of cyanide and of thiocyanate in the blood of all patients were measured. In seven of the patients the level of thiosulphate was also measured. Infusion of SNP on its own at levels exceeding 2 µg/kg/min led to the rising of cyanide levels in the blood being proportional to dosage. Infusion of SNP mixed with thiosulphate showed no such accumulation of cyanide in any patient, irrespective of dosage level and duration. The efficacy at lowering blood pressure was fully maintained in the mixed infusion. The elimination half-life for thiosulphate was 16.5 min. Pharmacokinetic calculation of the rise in cyanide level showed that mono-infusions of 5–10 µg SNP/kg/min could within 5–10 h cause a life-threatening cyanide level in the blood. By contrast, mixed influsion of SNP together with thiosulphate, for which light-opaque syringes and tubing must be used, is a procedure free of danger and should become the technique of choice when therapeutically administering SNP in order to lower blood pressure.Supported by the Deutsche Forschungsgemeinschaft     

Hyper-IL-6重组慢病毒对大鼠急性肝衰竭的保护作用

目的:探讨重组慢病毒介导的超级白细胞介素6(Hyper-IL-6)对大鼠急性肝衰竭的保护作用及机制。方法:45只D-氨基半乳糖急性肝衰竭模型大鼠随机分为3组:FIV-HIL-6组、FIV-IL-6组及未感染组,造模前2小时分别给予腹腔注射FIV-HIL-6、FIV-IL-6和生理盐水,造模后12、24、48、72小时及7天时进行肝功能、内毒素、肝组织脂质过氧化水平(MDA、SOD)及光镜、电镜检查,并用逆转录PCR检测7天时肝组织目的基因整合状况。另取16只正常大鼠随机分为2组,分别给予FIV-HIL-6、FIV(空载体)一次性腹腔注射,观察重组慢病毒对大鼠的毒副作用。结果:FIV-HIL-6组血清谷丙/草转氨酶(ALT/AST)、总胆红素(TB)、内毒素、MDA值低于FIV-IL-6组、未感染组,SOD值较高(P0.05),肝组织病变较轻;重组慢病毒对大鼠无明显毒副作用,大鼠肝脏组织中有目的基因Hyper-IL-6表达。结论:FIV-HIL-6成功转染大鼠肝脏组织,Hyper-IL-6对急性肝衰竭大鼠肝组织有明显的抗炎抗氧化作用,能有效改善大鼠肝功能及肝组织学状况,对急性肝衰竭大鼠具有保护和治疗作用。     

精胺对急性脑缺血再灌注损伤大鼠的保护作用

目的: 观察外源性精胺对急性脑缺血-再灌注损伤大鼠的作用,并初步探讨其可能机制。方法: 采用线栓法复制大鼠大脑中动脉缺血(2 h)-再灌注(2 h)模型。SD大鼠随机分为5组:假手术组、模型组和低、中、高剂量精胺组。检测指标有神经病学评分、脑梗死面积、皮层脑组织HE染色、电镜超微结构观察、超氧化物歧化酶活性(SOD)及丙二醛(MDA)含量。结果: 与模型组相比,不同浓度精胺均能降低大鼠急性脑缺血-再灌注后神经功能学评分、梗死面积、缺血脑组织MDA含量,减轻脑组织形态学和超微结构损伤,增加缺血区SOD活性。结论: 外源性精胺对大鼠局灶性急性脑缺血-再灌注损伤有保护作用,其机制可能与清除氧自由基有关。     

沉默微小RNA-218表达保护STZ诱导的糖尿病大鼠肾组织

目的:探讨沉默微小RNA-218(microRNA-218,miR-218)表达对链脲佐菌素(streptozotocin,STZ)诱导的糖尿病肾病大鼠肾脏组织的保护作用及其可能机制。方法:采用单次腹腔注射STZ(50 mg/kg)方法制备糖尿病大鼠模型并构建miR-218短发夹RNA(short hairpin RNA,shRNA)慢病毒载体。SD大鼠被随机分为健康对照组、糖尿病模型组、空载慢病毒组及miR-218-shRNA组。于自动生化仪上检测不同时点(4、8和12周)大鼠血糖、24h尿蛋白量、血清肌酐(serum creatinine,SCr)及血尿素氮(blood urea nitrogen,BUN)含量。实时荧光定量PCR(RTqPCR)检测肾脏组织miR-218的表达。RT-qPCR和Western blot检测血红素氧合酶1(heme oxygenase-1,HO-1)、肾病蛋白(nephrin)和p38丝裂原激活的蛋白激酶(p38 mitogen-activated protein kinase,p38 MAPK)的mRNA及蛋白表达水平。Caspase-3活性检测试剂盒检测caspase-3活性。末端脱氧核苷酸转移酶介导的dUTP缺口末端标记(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling,TUNEL)法检测肾脏组织细胞凋亡。结果:与健康对照组相比,STZ处理后大鼠miR-218表达水平显著升高。同时模型大鼠的血糖、24 h尿蛋白量、SCr及BUN含量显著升高(P0.05);模型大鼠肾脏组织中HO-1和nephrin的mRNA和蛋白表达水平显著降低,而p38 MAPK蛋白的磷酸化水平显著升高;另外,模型大鼠肾脏组织中的caspase-3活性也显著升高。模型大鼠感染miR-218-shRNA后,miR-218表达水平显著下降并可以显著逆转上述效应。miR-218-shRNA组肾脏组织细胞的凋亡水平显著低于糖尿病模型组及空载慢病毒组。结论:miR-218参与了糖尿病大鼠的肾脏损伤,慢病毒载体沉默其表达能有效抑制肾脏组织细胞的凋亡,提示miR-218可以作为糖尿病肾病的基因治疗靶点。     

硝普钠对急性胰腺炎大鼠治疗作用初探

目的与方法:为探索硝普钠对急性胰腺炎(AP)的治疗作用,采用胰管内注射牛磺胆酸钠溶液的方法建立大鼠AP模型,并用外源性一氧化氮(NO)供体硝普钠(SNP)实验性治疗,动态观察AP模型复制后(8、16、24、48h)血浆NO、超氧化物歧化酶(SOD)和淀粉酶含量的变化及胰腺组织学改变。结果:AP组血浆NO、SOD明显下降(P＜0.05),并持续24h以上,血浆淀粉酶含量明显升高(P＜0.05),而治疗组血浆NO、SOD明显高于非治疗组(P＜0.05),淀粉酶含量明显下降(P＜0.05)。治疗组胰腺组织病理损害明显轻于模型组。结论:大鼠实验性急性胰腺炎时,血浆NO含量、SOD活性明显下降,早期腹腔注射硝普钠能显著升高血浆NO、SOD含量,降低血浆淀粉酶含量,减轻胰腺病损。本实验为临床急性胰腺炎的早期治疗提供一新途径。