ARDS急性期大鼠心脏局部RAS的变化与BNP水平相关性研究

目的观察急性呼吸窘迫综合征（ARDS）急性期大鼠心脏局部肾素-血管紧张素系统（RAS）与脑钠素（BNP）水平的变化，并探讨其间的相关性。方法健康雄性sD大鼠54只，鼠龄12～16周，随机分为三组（每组18只）：假手术组（A组）仅进行气管切开插管和右颈总动脉穿刺置管，尾静脉注射生理盐水0．15mL／kg；ARDS未干预纽（B组）尾静脉注射油酸0．15mL／kg，建立油酸诱导的大鼠ARDS模型；ARDS机械通气治疗组（C组）VT-6mL／kg，RR=60次／min，Fi02—50％，I：E-1：2，PEEP=5cmH20。各组按造模成功后时间又分为a、b、C三个亚组，每组6只。于大鼠ARDS后1h、ARDS后2h、ARDS后4h取左室心肌组织放射免疫法检测血管紧张素I（AngI）、血管紧张素II（AngⅡ）含量及肾素（Renin）活性；ELISA测定血清中BNP水平。将数据进行统计学分析。结果同时间点与A组相比，B、C组AngI、AngII含量及Renin活性均显著增加（P〈0．05），血清BNP水平明显升高（P〈O．05）。同时间点C组与B组相比，C组AngI、AngII含量及Renin活性均有降低倾向，但差异无统计学意义（P〉0．05）。大鼠心肌局部AngⅡ含量及Renin活性与血清BNP含量呈正相关。结论ARDS可导致激活大鼠心脏局部的RAS。ARDS急性期大鼠心脏局部RAS的变化与BNP水平的变化呈正相关。

Correlativity study on variations of cardiac RAS and BNP in the acute stage of ARDS rat

Objective To observe the variations of cardiac RAS and brain natriuretie peptide （BNP） in the acute stage of ARDS in rat. Methods Fifty-four healthy male Sprague-Dawley rats with age of 12 -16 weeks were randomly divided into three groups. Group A was only tracheal intuba- tion, the right carotid artery catheterization, and tail vein injection of normal saline 0.15 mL/kg, n= 18. Group B was ARDS without intervention group which the building the ARDS model of rats in- duced by tail vein injection of oleic acid 0. 15 mL/kg, n= 18. Group C was ARDS with mechanical ventilation treatment group which the VT = 6 mL/kg, RR = 60 BPM, FiO2 = 50%, I ： E =1 ： 2, PEEP =5 cmHzO, n=18. Everygroup was randomly divided into 3 subgroups （a, b, c） on average at 1 h, 2 h and 4 h after rats showed ARDS. Ang Ⅰ , Ang Ⅱ content and the renin activity （Renin） were detected in left ventricular myocardial tissue by radioimmunoassay. The brain BNP were detected at the corresponding time points by enzyme linked immunosorbent assay （ELISA）. The results was an- alyzed. Results Compared group A with group B and C , Ang ]~ , Ang II content and renin activity were significantly increased（P〈0.05） and the level of BNP in serum were also significantly increased （P~0.05）. In each subgroup of group C, compared with group B, Ang Ⅰ , Ang Ⅱ content and renin activity were decreased （P〉0.05）. The results indicated that Ang Ⅱ content and renin activity of rats＇ myocardial tissue were positively correlated with BNP content. Conclusion ARDS could induce activation of cardiac local RAS in rats. Ang II content and renin activity of rats＇ myocardial tissue were positively correlated with BNP content in the acute stage of ARDS in rat model.