RDS过程PaO_2下降与肝、脑组织NO及ET动态变化关系探讨及形态学改变

Relation between gradual reduction of PaO_2 and dynamic changes of NO and ET of liver and brain

目的 :探讨油酸肺损伤所致RDS过程进行性氧分压下降与肝组织和脑组织一氧化氮、内皮素动态变化之间的关系 ,为单纯肺损伤对其它脏器的继发性损害提供实验依据 .方法 :日本大耳白兔 30只 ,雌雄不拘 ,其中 5只作为对照组 ,另 2 5只从耳缘静脉缓慢注入油酸 0 .1mL/kg,以 30、6 0、90和1 2 0min为时限并分组实验 .检测平均动脉血压 (MABP)、血气以及血浆、肝组织和脑组织一氧化氮 (NO)、内皮素 (ET)的动态变化 .同时进行肝、脑组织电镜观察 .结果 :实验组动脉氧分压 (PaO2 )和MABP随时间延长呈进行性下降 (P <0 .0 1 ) .二者之间呈正相关关系 (r=0 .96 ,P <0 .0 1 ) ;肝组织一氧化氮合酶 (NOS)和脑组织NO含量在油酸注入后 30min时代偿性增加 (P <0 .0 1 ) ,而从 6 0min后又逐渐降低 .肝组织ET含量在注射油酸 30min到 90min随时间延长而逐渐增加 (P <0 .0 5 ) .在 1 2 0min时显著降低 (P <0 .0 5 ) .脑组织ET含量在油酸 30min时显著下降 (P <0 .0 1 ) ,而从 6 0min后又逐渐上升 ,与 30min组相比P值均 <0 .0 5 .电镜下 ,油酸 90min和油酸1 2 0min组可见肝、脑细胞核形状不规则 ,核周隙增宽 ;线粒体肿胀 ,嵴断裂、嵴消失 ;高尔基复合体扩张 ;胞质中可见坏死灶和髓样结构 .结论 :油酸所致单纯肺损伤 (RDS)

AIM: To investigate the dynamic changes of levels of No and ET of liver and brain during the gradual reduction of PaO 2 in rabbits so as to provide theoretic basis for secondary damage of other organs in the acute lung injure. METHODS: The RDS of rabbits was established by injecting OA in vein. The PaO 2, NO and ET of liver and brain were detected and the ultramicrostructure of the liver and brain was observed under the electron microscope. RESULTS: PaO 2, MABP of OA groups decreased. The levels of NOS in the liver and NO in the brain increased in OA 30 min group ( P <0.01), but it decreased in 60 min and later groups ( P <0.01). The levels of ET in the liver increased in 30 min and 90 min groups ( P <0.01) but decreased in 120 min group. The level of ET in the brain decreased in 30 min group ( P <0.01) and increased in 60 min and later groups ( P <0.05). The ultramicrostructure of the liver and the brain changed under the electron microscope in OA 90 min and 120 min groups. CONCLUSION: The liver and brain are damaged secondarily during RDS in the rabbits and the damage is associated with the reduction of PaO 2 and MABP and the levels of NOS and ET.