论文部分内容阅读
目的探讨选择性阻断环鸟苷酸依赖性蛋白激酶Ⅰ(PKG-Ⅰ)对脓毒性休克大鼠血管低反应性的影响。方法将雄性Sprague-Dawley大鼠随机分为假手术组(SHAM组)、模型组(CLP组)、一氧化氮合成酶抑制剂组(L-NAME组)和PKG-Ⅰ特异性抑制剂组(DT-2组),每组20只。采用盲肠结扎穿孔法建立脓毒症模型,每组分别于造模后2、4、6h各取5只大鼠,分离胸主动脉制成血管环,L-NAME组和DT-2组血管在检测前分别与L-NAME或DT-2孵育30min。观测血管环对苯肾上腺素(PE)的浓度梯度效应曲线、最大收缩力(Emax)及产生Emax的半数有效浓度(EC50)。于造模后4h,每组各另取5只大鼠分离胸主动脉,采用光谱法定量检测其PKG-Ⅰ活性。结果造模后2、4、6h,CLP组的血管环收缩功能均显著低于SHAM组和L-NAME组(P值分别<0.05、0.01);造模后6h,L-NAME组显著低于SHAM组(P<0.05);造模后4h,DT-2组显著高于CLP组(P<0.05)。与SHAM组比较,CLP组造模后2、4、6h的Emax值均显著降低,但EC50值均显著升高(P值分别<0.05、0.01)。与CLP组比较,L-NAME组造模后2、4、6h的Emax值均显著升高,EC50均显著降低(P值分别<0.05、0.01)。DT-2组造模后4h的Emax值较CLP组显著升高,EC50显著降低(P值分别<0.05、0.01)。造模后4h,CLP组的PKG-Ⅰ活性值(0.905)较SHAM组(0.640)显著升高(P<0.01),L-NAME组及DT-2组的PKG-Ⅰ活性值(0.672、0.724)均较CLP组显著降低(P值均<0.05)。结论选择性阻断PKG-Ⅰ可部分恢复脓毒症大鼠血管环低反应性。
Objective To investigate the effect of selective blocking of cyclic guanylate-dependent protein kinase Ⅰ (PKG-Ⅰ) on vascular hyporeactivity in septic shock rats. Methods Male Sprague-Dawley rats were randomly divided into sham operation group (SHAM group), model group (CLP group), nitric oxide synthase inhibitor group (L-NAME group) and PKG-Ⅰ specific inhibitor group DT-2 group), 20 in each group. The cecal ligation and perforation method was used to establish the sepsis model. Rats in each group were sacrificed at 2, 4, and 6 h after modeling respectively. The thoracic aorta was separated into vascular rings. The blood vessels in L-NAME group and DT-2 group were Before testing, incubated with L-NAME or DT-2 for 30 min respectively. The concentration gradient effect curve, maximum contractile force (Emax), and EC50 of Emax of vascular rings on phenylephrine (PE) were observed. At 4h after modeling, 5 rats in each group were randomly divided into 5 groups: the thoracic aorta was separated and the PKG-Ⅰ activity was detected by spectrometry. Results The systolic function of vascular rings in CLP group was significantly lower than those in SHAM group and L-NAME group (P <0.05, 0.01 respectively) at 2, 4 and 6 h after model establishment. In L-NAME group 6 h after modeling, SHAM group (P <0.05); 4h after modeling, the DT-2 group was significantly higher than the CLP group (P <0.05). Compared with the SHAM group, the Emax values at 2, 4 and 6 h after CLP were significantly decreased, but the EC50 values were significantly increased (P <0.05 and 0.01 respectively). Compared with the CLP group, the Emax values at 2, 4, and 6 hours after LPS modeling in L-NAME group were significantly increased, while the EC50 values were significantly lower (P <0.05, 0.01 respectively). The Emax values at 4h after modeling in DT-2 group were significantly higher than those in CLP group, while the EC50 values were significantly lower (P <0.05, 0.01 respectively). PKG-I activity in CLP group (0.905) was significantly higher than that in SHAM group (0.640) (P <0.01) at 4h after modeling, and PKG-I activity in L-NAME group and DT- ) Were significantly lower than those in CLP group (P <0.05). Conclusion Selective blocking of PKG-Ⅰ partially regresses vascular ring hyporeactivity in septic rats.