Expression Of Vascular Endothelial Growth Factor And Placental Growth Factor In The Placenta Tissue Of Preeclampsia And Eclampsia Patients

Objective Hypertensive disorder complicating pregnancy is a commoncomplication of pregnancy. This disorder is still one of the leading causes ofmaternal and fetal morbidity and mortality .At present its cause remains obscure,so as far there is no proven way to prevent this disease. Preeclampsia is a triadof edema, hypertension, and proteinuria occurring primarily in nulliparas afterthe 20th gestational week and most frequently near term. Eclampsia is theoccurrence of seizures that cannot be attributed to other causes in a preeclampticpatient. To discuss the pathogenesis of preeclampsia is still an important task inobstetric field. At present the theories of endothelial cell injury and shallowinvasion of the maternal spiral arteries by cytotrophoblasts are supported widely.Vascular endothelial growth factor (VEGF) is an effective angiogenic growthfactor capable of inducing proliferation, migration and activation of endothelialcells and stimulating vascular permeability. Placenta growth factor (PLGF)belongs to the VEGF family and is able to improve proliferation of trophoblast,migration and activation of endothelial cells, too. The purpose of this study is todiscuss the expressions of VEGF / PLGF throughout normal pregnancy and inpatients with preeclampsia and eclampsia as well as to explore the relationshipbetween VEGF /PLGF and pathogenesis of hypertensive disorder complicatingpregnancy.Method: Placental tissue samples were collected from 80 healthypregnant women as a control group and 60 patients composed of 20 mildpreeclampsia, 20 severe preeclampsia and 20 eclampsia as tested groups. Allspecimens came from the Second Hospital of Jilin University (2003--2004).Immunohistochemical method was used to detect the density of expresstion ofVEGF and PLGF protein.Result's standard: Observing results made use of double blindprocedure .The positive expressions of VEGF/PLGF showed brown particles incytoplasm or nucleus. Refer to Hao's comprehensive scoring method: observethe distribution, positive strength and positive rate of VEGF/PLGF protein. Firstaccording to the degree of stain score zero, one, two and three respectively.Second according to percent of positive cell score zero(65%) respectively. When half of the sum ofpercent of positive cell and degree of stain is <0.5,response to immunization isnegative , 0.5～1 is positive , 1.5～3 is strongly positive.Use software SPSS11.5 to analyze results of immunohistochemistry andmake use of X2 test to compare rate among these groups.Results: 1.The distribution of VEGF/PLGF: The distributions of the twofactors in placenta tissues between two groups weresimilar. Specific pigmentingof VEGF was mainly in trophoblast, next in decidua and endothelial cell ofcapillary, the positive cell also could be observed in stroma. PLGF was mainlydistributed in trophoblast, next in decidua ,the positive cell also could beobserved in stroma and endothelial cell of capillary. The expression of the twofactors in patients with preeclampsia or eclampsia were significantly reducedthan those in normal pregnant women(P<0.05).2. Influence of disease severity on VEGF /PLGF density in women withpreeclampsia and eclampsia : There was a trend that the density of expression ofthe two factors in preeclampsia and eclampsia group decreased with theseverity of disease. Although there was no significant difference of densitybetween severe preeclampsia and eclampsia group(P>0.05). Density wasreduced significantly in women with severe preeclampsia than those in womenwith mild preeclampsia (P<0.05) . Density was reduced significantly in womenwith eclampsia than those in normal pregnant women (P<0.05 ) .conclusion:1 The distribution of the two factors in normal placenta tissuessuggested that they play important roles in placental physiology throughouthealthy pregnancy.2,The expression of the two factors in patients with pre-eclampsia oreclampsia were significantly reduced than those in normal pregnant women(P<0.05﹚. This revealed decreased production of VEGF/PLGF may compromiseendothelial cell and trophoblast functions and further contribute to the vascularpathobiologic characteristics noted in preeclampsia and eclampsia .3,There was a trend that the density of expression of the two factors inpreeclampsia and eclampsia group decreased with the severity of disease .Thedensity of expression of the two factors by immunohistochemical methodreflects the severity of eclampsia at a certain extent.