Hoque A M, Papapetropoulos A, Venema R C, Catravas J D, Fuchs L C
Vascular Biology Center and Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta, Georgia 30912, USA.
Am J Physiol. 1998 Sep;275(3):H1078-83. doi: 10.1152/ajpheart.1998.275.3.H1078.
Lipopolysaccharide (LPS) causes impaired vascular contractility proposed to be mediated by induction of nitric oxide synthase (iNOS). Antisense (AS) oligonucleotide inhibits the translation of target mRNA into functional proteins. We hypothesize that in vivo pretreatment with AS oligonucleotide targeted to iNOS mRNA can prevent LPS-induced hyporeactivity to norepinephrine (NE). Three groups of conscious male Wistar rats received one of the following: saline, AS, or mismatch (MM) oligonucleotide at 0.4 mg/kg iv at 12 and 24 h before LPS (5 mg/kg iv). The fourth group received saline only. Mean arterial pressure (MAP) and heart rate (HR) were continuously recorded before and 6 h after LPS or saline administration. Aorta, lung lavage, and lung tissue were collected for determination of iNOS protein expression and NOS activity. Small mesenteric arteries ( approximately 250 micron) were isolated, denuded of endothelium, and maintained at a constant intraluminal pressure of 40 mmHg for study in vitro. LPS produced significant tachycardia that was not altered by AS or MM oligonucleotide. AS, but not MM oligonucleotide, reduced the accumulation of cGMP, the increase in conversion of L-[3H]arginine to L-[3H]citrulline, and iNOS protein expression in tissue from LPS-treated rats. Small mesenteric arterial contraction to NE was significantly impaired in vessels from LPS-treated rats and was restored by AS, but not MM, oligonucleotide. In a rat model of septic shock, AS oligonucleotide to iNOS mRNA inhibits NOS activity and iNOS protein expression and prevents the vascular hyporeactivity to NE, which may contribute to hypotension in shock.
脂多糖（LPS）可导致血管收缩功能受损，这一过程被认为是由一氧化氮合酶（iNOS）的诱导介导的。反义（AS）寡核苷酸可抑制靶mRNA翻译成功能性蛋白质。我们假设，用靶向iNOS mRNA的AS寡核苷酸进行体内预处理可预防LPS诱导的对去甲肾上腺素（NE）反应性降低。三组清醒雄性Wistar大鼠在LPS（5 mg/kg静脉注射）前12小时和24小时接受以下处理之一：生理盐水、AS或错配（MM）寡核苷酸，剂量为0.4 mg/kg静脉注射。第四组仅接受生理盐水。在给予LPS或生理盐水之前和之后6小时连续记录平均动脉压（MAP）和心率（HR）。收集主动脉、肺灌洗液和肺组织以测定iNOS蛋白表达和NOS活性。分离小肠系膜动脉（约250微米），去除内皮，并维持管腔内压力恒定为40 mmHg用于体外研究。LPS引起显著的心动过速，AS或MM寡核苷酸对此无改变。AS寡核苷酸而非MM寡核苷酸可减少LPS处理大鼠组织中cGMP的积累、L-[3H]精氨酸向L-[3H]瓜氨酸转化的增加以及iNOS蛋白表达。LPS处理大鼠的血管对NE的小肠系膜动脉收缩明显受损，AS寡核苷酸而非MM寡核苷酸可使其恢复。在脓毒性休克大鼠模型中，针对iNOS mRNA的AS寡核苷酸可抑制NOS活性和iNOS蛋白表达，并预防血管对NE的反应性降低，这可能导致休克中的低血压。
