Expression of inducible nitric oxide synthase (iNOS) mRNA in target organs of lethal and non-lethal strains of murine malaria

Nitric oxide (NO) is a putative mediator of the immunological and/or pathological responses to malaria, consequently it is a potential target for novel drug therapy. Numerous cell types increase expression of inducible nitric oxide synthase (iNOS) under inflammatory conditions, the most relevant stimuli being cytokines and endotoxins. In this study the expression of iNOS mRNA in several target organs (brain, liver, spleen) of malaria have been investigated in MF1 mice during lethal Plasmodium (P.) berghei and non-lethal P. c. chabaudi infection. In P. berghei malaria, iNOS mRNA decreased in liver and was unchanged in spleen during the period of rising parasitaemia, but increased in both organs late in the infection, when parasitaemia was high and death imminent. In mice infected with P. c. chabaudi, spleen iNOS mRNA increased progressively throughout the early, peak and recovery periods of parasitaemia, but decreased in liver. Brain iNOS mRNA decreased in samples collected throughout the time courses of both infections. Hence it is evident that changes in iNOS mRNA in murine malaria depend upon the tissue, day of infection, degree of parasitaemia and strain of Plasmodium. These data indicate induction of iNOS mRNA in the spleen has a role in combating these strains of Plasmodium in MF1 mice. Failure to clear lethal P. berghei parasitaemia was associated with increased iNOS mRNA expression in the liver, which may contribute to the pathology of this malaria.     

褪黑素对急性百草枯中毒大鼠肺组织核因子-κB及诱导型一氧化氮合酶的影响及治疗作用的研究

目的 观察褪黑素(MT)治疗前后急性百草枯(PQ)中毒大鼠肺组织中核因子-κB(NF-κB)及诱导型一氧化氮合酶(iNOS)表达的变化,探讨它们在百草枯所致肺损伤中的作用.方法 将45只SD大鼠随机分为染毒组、MT治疗组和对照组.3 d后分别测定三组大鼠血清中一氧化氮(NO)及丙二醛(MDA)含量,同时取大鼠肺组织,采用电泳迁移率改变分析法(EMSA)检测NF-κB活性;RT-PCR检测iNOSmRNA的表达.结果 大鼠肺组织NF-κB活性及iNOS mRNA的表达在染毒组明显高于对照组(P＜0.01).经MT治疗后显著降低(P＜0.01),但仍高于对照组(P＜0.01).染毒组大鼠血清中NO及MDA的浓度较对照组明显升高(P＜0.01),经MT治疗显著降低(P＜0.01).结论 NF-κB及iNOS在百草枯所致大鼠肺损伤中起重要作用;MT能减少染毒大鼠肺组织NF-κB的激活,降低其调控的iNOS活性,减轻染毒大鼠肺组织损伤.     

Electro-acupuncture on the iNOS of lumbar intervertebral disk tissues in rats

目的：探讨电针防治腰椎间盘移位的机理。方法：75只大鼠经手术造成椎间盘移位模型，成功后分为电针组，西药组，针药组，模型对照组和正常对照组，分别给予相应处理。RTPCR法测定椎间盘组织中iNOSmRNA的表达。结果：模型组犬鼠椎间盘组织iNOSmRNA表达与正常组之间比较存在显著性差异（P〈0．01）；电针组、西药组、针药组对大鼠椎间盘组织iNOSmRNA表达均受抑制，与模型组比较有显著性差异（P〈0．01）。结论：电针具有抑制椎间盘组织内iNOS的作用。     

复方三酮脑通片对MCAO大鼠脑组织形态学的影响

目的:试验观察复方三酮脑通片对MCAO大鼠脑组织形态学改变的影响,探讨其对缺血性脑血管疾病脑组织形态学的保护作用。方法:采用栓线法复制大脑中动脉栓塞(MCAO)模型,造模成功后随机分为六组给药,HE切片观察脑组织细胞形态学及脑梗死面积的变化,并采用免疫组化技术对脑血管内皮细胞与神经细胞的诱导型一氧化氮合酶(iNOS)的表达进行检测。结果:在MCAO大鼠急性脑缺血恢复过程中,复方三酮脑通片明显降低海马CA1区神经元细胞的死亡率及神经细胞iNOS的表达,促进局部微血管的生成,加速MCAO大鼠脑功能的恢复。结论:复方三酮脑通片能够降低急性脑缺血MCAO大鼠脑缺血局部神经元的死亡率。促进局部微血管的生成,改善脑组织微循环,并下调缺血脑组织神经元iNOS的表达。     

清肺化痰通络方对大鼠肺纤维化肺组织中iNOS表达的影响

目的：观察清肺化痰通络方对博莱霉素所致大鼠肺纤维化中诱导型一氧化氮合酶（iNOS）表达的影响。方法：通过气管内灌注博莱霉素A5（BLMA5）复制大鼠肺纤维化动物模型，于灌服该方后3、7、14、28天，分别观察肺组织病理变化及iNOS的表达。结果：清肺化痰通络方能显著改善大鼠的一般身体状况，减轻病变的程度，并抑制iNOS的表达。结论：清肺化痰通络方可能通过抑制iNOS的异常表达。对BLMA5致肺组织纤维化起到一定的防治作用。     

三七总皂甙对大鼠脊髓损伤后iNOS表达及细胞凋亡的影响

目的探讨大鼠脊髓损伤后应用三七总皂甙对诱导型一氧化氮合酶(iNOS)表达及细胞凋亡的影响。方法采用Allen’s法将64,只成年SD大鼠造成脊髓中度损伤模型,再随机分为损伤组和三七总皂甙组,分别给予生理盐水及三七总皂甙注射液治疗,损伤后不同时间点(1、3、7、14d)处死大鼠,用HE染色观察损伤脊髓组织病理变化,用免疫组化染色检测iNOS阳性细胞,原位末端标记法(TUNEL法)标记凋亡细胞。结果HE染色镜检发现脊髓组织病理学改变三七总皂甙组明显轻于损伤组;两组均发现iNOS表达及凋亡细胞,且损伤组iNOS表达及神经细胞凋亡指数均高于三七总皂甙组(P<0．05)。结论三七总皂甙注射液能抑制脊髓损伤后iNOS表达及神经细胞凋亡。     

Comparative researches on effects of sodium dodecylbenzene sulfonate and sodium dodecyl sulfate upon Lateolabrax japonicus biomarker system

Fish Lateolabrax japonicus were exposed to anion surfactant sodium dodecylbenzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS) at 1 mg/l, respectively, for 6, 12 and 18 d, with one control group. Liver antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and glutathione S-transferase (GST) were determined; brain acetylcholinesterase (AChE) and liver inducible nitric oxide synthase (iNOS) activities were also measured. The results of the study indicated that these parameters made different, sometimes, adverse responses to SDBS and SDS exposure, such as the activity of iNOS can be inhibited by SDBS and induced by SDS, the different physico-chemical characteristics of SDBS and SDS should be responsible for their effects on enzyme activities.     

Ketamine inhibits lipopolysacharide (LPS) induced gastric luminal fluid accumulation

INTRODUCTION: Lipopolysacharide (LPS) causes gastrointestinal ileus and gastric luminal fluid accumulation. Ketamine, an anti-inflammatory anesthetic agent attenuates accumulation of luminal fluid. However, its effects on gastrointestinal transit induced by endotoxemia are unknown. The purpose of this study was to determine if the anti-inflammatory properties of ketamine improve impaired gastric emptying and gastrointestinal transit because of LPS. MATERIALS AND METHODS: Rats were given ketamine (70 mg/kg i.p.) or saline 1 h before LPS (20 mg/kg, i.p.) or saline injection. Five hours after LPS injection, rats were gavaged with 1 cc consisting of 0.1 ml of 5 mm FITC Dextran added to 0.9 ml of saline. After 30 min, rats were sacrificed, and gastric emptying, gastrointestinal transit, and gastric fluid accumulation determined. Gastric and ileal mucosa were harvested for analysis of inducible nitric oxide synthase (iNOS) (Western immunoblot). Results are reported as mean +/- SE (n > or = 5 per group; ANOVA). RESULTS: Ketamine did not prevent LPS induced gastrointestinal ileus, nor did it improve gastric emptying. More importantly, it did not worsen gastrointestinal function or gastric emptying when compared to saline controls. However, it did decrease LPS induced gastric luminal fluid accumulation and blunted iNOS expression in both the stomach and ileum. CONCLUSION: These data indicate that the ability of ketamine to attenuate gastric fluid accumulation is not because of improved gastric emptying or improved gastrointestinal transit. Moreover, while iNOS may play a role in LPS induced gastric luminal fluid accumulation, it does not appear to be a major mediator of the gastrointestinal ileus caused by LPS.