The Change Of Endogenous Heme Oxygenase-carbon Monoxide Systerm Activity In Plasma And Placenta Of PIH

Objective:Pregnancy induced Hypertation (PIH),a frequent severe disease is extremely harmful for the safety of mother and baby. Its mechanism has not been completely elucidated yet. However,it is a confirmation that PIH is related with the endothelial cell injury. Edothelins,nitricoxide synthase/ nitricoxide prostacyclin/thromboane play an important role in the pathogenesis of PIH. Studies on animals have shown that the heme oxygenase/ carbon monoxide(HO/CO) system plays an important role in regulating blood pressure. HO catalyzes heme to procuce CO,bilirubin and Fe2+. CO is strong vasodilative . however,the state of the system ability in PIH patients is still poorly unserstood. Heme is one of the most potent catalyst forlipid peroxidation. The induction of HO expression leads to the increase of free heme and free radical,resulting in extensive injury of biological membrane,endothelial dysfunction and large amount of vasoconstrictive agents release. In this work,HO-1,CO,SOD,LOOH in plasma and HO-1 in placenta were detected to investigate the HO/CO system and the oxidative/anti-oxidative ability in comparing to normal non-pregnant women,normal pregnant women and PIH women.Methods:Plasma and placentas were collected from PIH patients,non-pregnant and normal pregnant women in Hexian memorial hospital and Nanfang hospital. The contents of HO-1,CO,LOOH in plasma were determined by a sandwich ELISA method,Chalmers hemoglobin method,and FOX method respectively. Plasma SOD content was performed with the commercially available detection kit. The expression of HO-1 in placentas were detected by the method of immunohisto chemistry.Results:l.The levers of HO-1,CO and SOD in the term -pregnant group were signifacantly higher than those in thenon-pregnant group (2.30 + 0.25 VS 0.96 + 0. 15,p (0.01) . 2. The contents of HO-1 and CO in PIH group decreased graduelly with the severity of patients incressed,especially in the severe PIH patients (P<0.01). 3. The HO-1 staining in the placents obtained from moderate and severe PIH patients was more intensive than that in normal pregnanies. The staining areas,positive units in moderate and severe PIH placents were also higher(p<0.01). 4. Plasma SOD and LOOH was significantly high in normal pregnanies comparing to non-pregnanct women(p<0.05). The plasma levels of SOD and LOOH were higher in moderate and severe PIH patients than those in normal pregnant women(P<0.01). 5. A signifant negative linear correlation was found between the plasma contents of HO-1 and LOOH in PIH patients(r=-0.689,-0.942,p<0.01). 6.The severity of PIH was negatively correlated with the levers of endogenous HO-l,CO,SOD(r=-0.825,-0.861,-0.865,p<0.01), positivelycorreelated with the lever of LOOH(r=0.985,p<0.01).Conclusions:1. The HO-1/CO content increaed in normal pregant women,with might be a compensation change for theincresing of blood volume. 2. The levels of HO-1 and CO were signifanctly dereased in PIH compared with normal pregnanies,The contents of HO-land CO in PIH group decreased graduelly with the severity of patients increased,especilly in the severe PIH patients. Plasma HO and CO might play an important role in the pathogenesis of PIH. 3. HO-1 expression in placentas was elevated in moderate and severe PIH patients,which might be a compensation change. 4. Endogenous HO might be one of the antagonists of LOOH in the pathogenesis of PIH.