【摘要】 目的:探讨雾化吸入一氧化氮供体亚硝酸钠(NaNO2)后对低氧性肺动脉高压(HPH)大鼠肺动脉压力及体内一氧化氮(NO)、硫化氢(H2S)水平的影响。方法:雄性Wistar大鼠50只,随机分为常氧空白组、常氧亚硝酸钠组、低氧空白组、低氧生理盐水组、低氧亚硝酸钠组,采用常压低氧法建立大鼠HPH动物模型。测定肺动脉平均压(mPAP)、右室重量、左室+室间隔重量并计算右心室肥厚指数(RVHI=RV/LV+S);血清及肺匀浆NO含量、血浆H2S水平测定;光镜观察肺小动脉结构改变,弹力纤维+VG染色观察弹力纤维、肌纤维及胶原纤维增生情况。结果:低氧前各组大鼠体重无差别,而低氧后大鼠体重差别显著(P<0.05);低氧各组大鼠的mPAP、RVHI值与常氧各组相比均升高,低氧亚硝酸钠与低氧空白组和低氧生理盐水组比较,mPAP和RV/(LV+S)值降低(P<0.05);血清中NO水平低氧各组较常氧各组均降低(P<0.05);肺组织匀浆中NO水平:低氧空白组和低氧生理盐水组较常氧各组降低(P<0.05);而低氧亚硝酸钠组与常氧空白组比较无显著差异(P>0.05);血中H2S水平:低氧各组均较常氧各组降低(P<0.05);低氧亚硝酸钠组与低氧空白组、低氧生理盐水组比较升高(P<0.05)。光镜下,常氧空白组管腔结构正常;常氧亚硝酸钠组未见明显变化;低氧空白组肺小动脉平滑肌增生,胶原纤维增多,管壁增厚,管腔狭窄;低氧生理盐水组变化同低氧空白组;低氧亚硝酸钠组管壁狭窄较低氧空白组有所减少。结论:雾化吸入亚硝酸钠能有效降低肺动脉压力,减轻右室重构,可调节大鼠体内NO、H2S水平,可能通过直接作用或在体内影响气体信号分子的分泌及合成来实现对HPH的防治。更多还原

【Abstract】 AIM:To observe the change of nitric oxide(NO)and hydrogen sulfide(H2S)in blood and lung homogenate of hypoxic pulmonary hypertension(HPH)rat model,and to discuss the meaning of inhalation sodium nitrite and these factors in the treatment of HPH. METHODS:Fifty healthy male Wistar rats were assigned randomly into 5 groups(10 rats each):normoxia control group(NC),normoxia sodium nitrite group(NNI),hypoxic control group(HC),hypoxic normal saline group(HNS)and hypoxic sodium nitrite group(HNI). The mean pulmonary arterial pressure(mPAP),weight of right ventricle,weight of left ventricle plus septum,and the ratio of the weight of right ventricle to that of left ventricle plus septum(right ventricle hypertrophy index,RVHI)were also determined. The serum level of NO and plasma level of H2S were measured,and at the same time the levels of NO in the lung homogenate were detected. The structures in pulmonary arteries were examined using optical microscope. RESULTS:After model established,compared to that in the normoxia groups,the body weight decreased significantly in hypoxia groups(P<0.05),although no difference of body weight in five groups before producing model was observed. Compared to that in normoxia groups,the levels of mPAP and RVHI increased significantly in hypoxia groups,and compared to that in hypoxia control groups and hypoxia normal saline group,mPAP and RVHI levels decreased significantly in hypoxia sodium nitrite group(P<0.05). Compared to that in normoxia groups,the serum level of NO decreased significantly in hypoxia groups(P<0.05). NO level in lung homogenate decreased significantly in hypoxia control group and hypoxia normal saline group as compared to that in normoxia groups(P<0.05),and no obvious difference between hypoxic sodium nitrite group and normoxia groups was found. The plasma level of H2S was decreased significantly in hypoxia groups(P<0.05)as compared to that in normoxia groups. H2S level increased significantly in hypoxia sodium nitrite group as compared to that in hypoxia control groups and hypoxia normal saline group(P<0.05). Observation under optical microscope,the lumen structure of lung in normoxia control group was normal. No significant change in normoxia sodium nitrite group was found. The proliferation of smooth muscle cells(SMCs),the collagen fiber deposition in the vessel wall and every caliber thickening was observed in hypoxic control group. The same changes were also observed in hypoxic normal saline group. The thickened caliber was relieved significantly in hypoxic nitrite group. CONCLUSION:Pulmonary hypertension and right ventricle reconstitution can be relieved by inhalation of sodium nitrite,and can be regulated by the level of NO and H2S in rats. Above all,inhalation of sodium nitrite may degrade HPH directly or by affecting the externalization and synthesizing of gas signaling molecule indirectly.更多还原