摘要
探讨谷氨酰胺(Gln)对脂多糖(LPS)致大鼠心功能障碍的保护作用。雄性健康清洁级大鼠45只,随机分为对照组(NS5ml)15只、LPS组(10mg/kg)15只、Gln(1g/kg)治疗组15只,腹腔注药后24h测定平均血压(MAP)、左室收缩末期压力(LVESP)、左室压力上升及下降最大变化速率(±dp/dtmax)等心功能指标;观察心肌病理变化,并分别用RT-PCR及Western blot方法测定Toll样受体4(TLR4)、核因子κB(NF-κB)及TNF-αmRNA及蛋白表达;ELISA检测心肌TNF-α含量。结果显示:LPS增高大鼠心肌TLR4、NF-κB及TNF-α表达及心肌TNF-α含量,同时导致左室功能减退。Gln可下调心肌TLR4、NF-κB及TNF-α表达,使心肌TNF-α含量下降,并部分改善左室功能。提示Gln对LPS致心肌损伤具有一定保护作用,其机制之一可能与抑制TLR4-NF-κB信号转导通路有关。
To explore the mechanism of the protective effect of glutamine（Gln） on lipopolysaccharide（LPS）-induced myocardial injury of rats,45 clean-grade healthy male rats were randomly divided into three groups：15 in control group（NS 5 ml）,15 in LPS-treated group（10 mg/kg） and 15 in Gln treated group（1g/kg）. The functional indexes of heart,such as the mean arterial pressure（MAP）,left ventricular end systolic pressure（LVESP） and rise and decline of the maximum velocity of intraventricular pressure（±dp/dt max）were examined 24 hrs after abdominal injection. and the pathological changes of myocardium were observed under light microscope. The toll-like receptor 4（TLR4）,nuclear factor κB（NF-κB） and TNF-α mRNA and the protein expression were assayed by RT-PCR and Western blot assay. Levels of myocardial TNF-α were determinated by ELISA. It was demonstrated that LPS could increase the expressions of TLR4,NF-κB,TNF-α,mRNA in rat myocardium,thus reducing the content of myocardial TNF-α protein and partially improve the function of left ventricle. From these results,it is clear that Gln has certain protective effect on the LPS-induced myocardial injury and one of its mechanism may be associated with the inhibition of TLR4-NF-κB signal transduction pathway.
出处
《现代免疫学》
CAS
CSCD
北大核心
2010年第4期308-312,共5页
Current Immunology
基金
国家自然科学基金资助项目(30670836)
