Maternal circulating nitrite levels are decreased in both normal normotensive pregnancies and pregnancies with preeclampsia.

OBJECTIVE: To evaluate whether maternal nitric oxide synthesis in pregnancies with preeclampsia is different from that in normal normotensive pregnancies. MATERIALS: Maternal circulating combined nitrate and nitrite levels or nitrite level were compared between 10 normotensive nonpregnant women, 30 normotensive pregnant women (10 first-trimester, 10 second-trimester, and 10 third-trimester pregnancies), 20 normotensive postpartum women (10 at 1 week after delivery, and 10 at 4 weeks after delivery), and 13 preeclamptic women (32 to 40 weeks' gestation). End-products of nitric oxide synthesis were measured from maternal venous blood samples using a fluorometric assay. RESULTS: Maternal circulating nitrite levels in nonpregnant women (1.13 +/- 0.22 microM) were significantly higher than those in the first-trimester pregnant women (0.68 +/- 0.13 microM), second-trimester pregnant women (0.65 +/- 0.13 microM), third-trimester pregnant women (0.48 +/- 0.17 microM), first puerperal week women (0.36 +/- 0.16 microM), and fourth puerperal week women (0.67 +/- 0.17 microM), respectively (p < 0.05). Maternal circulating nitrite level was decreased with advancing gestation, still remained low just after delivery, and was increased 4 weeks later. There was no significant difference in maternal circulating nitrite level between preeclamptic women (0.40 +/- 0.17 microM) and third-trimester pregnant women (0.48 +/- 0.17 microM). However, there were no significant differences in maternal circulating combined nitrate and nitrite levels among the groups. CONCLUSION: These results suggest that the maternal nitric oxide synthesis is not changed in normal normotensive pregnancies and pregnancies with preeclampsia. However, plasma nitrite level, which has stronger spasmolytic activity than the activity of the nitrate, was decreased in both normal normotensive pregnancies and pregnancies with preeclampsia.     

Human chorionic gonadotropin and testosterone in normal and preeclamptic pregnancies in relation to fetal sex

OBJECTIVE: The aim of the present study was to evaluate the effects of fetal gender on serum human chorionic gonadotropin (hCG) and testosterone in normotensive and preeclamptic pregnancies. METHODS: The study consisted of 137 women with singleton pregnancies in the third trimester. Seventy-three pregnancies were uncomplicated; among those were 35 male and 38 female fetuses. Sixty-four pregnancies were complicated by preeclampsia; among those were 33 male and 31 female fetuses. Human chorionic gonadotropin and total testosterone were measured in maternal peripheral blood. RESULTS: In male-bearing pregnancies, maternal hCG and testosterone serum levels were significantly higher in preeclamptic than normotensive mothers (P <.001). In female-bearing pregnancies, testosterone levels were significantly higher in preeclamptic than normotensive mothers (P <.001), whereas the hCG levels were not significantly different. Male-bearing preeclamptic women had significantly higher testosterone levels than female-bearing preeclamptic women (P <.02), whereas the hCG levels were not significantly different. In uncomplicated pregnancies the hCG levels were significantly higher in female-bearing than in male-bearing mothers (P <.005), whereas the testosterone levels were not significantly different. CONCLUSION: In preeclamptic pregnancies with male fetuses, the maternal serum hCG levels were significantly higher than in uncomplicated pregnancies. Total testosterone levels were significantly higher in pregnancies with either gender and significantly higher in male-bearing than in female-bearing pregnancies. This may indicate an androgen influence on the pathophysiologic mechanism of preeclampsia.     

Plasma endothelin levels in preeclampsia: elevation and correlation with uric acid levels and renal impairment.

OBJECTIVE: The purpose of this study was to determine if endothelin levels are elevated in women with preeclampsia and if these levels correlated with other laboratory features of disease severity. STUDY DESIGN: Parameters were compared in four groups of women volunteers by means of analysis of variance: (1) 16 women with preeclamptic pregnancies, (2) 11 pregnant women without preeclampsia, of similar lengths of gestation, (3) six otherwise normal women with pregnancies at term or beyond (greater than 38 weeks), and (4) 22 normotensive young women. RESULTS: Endothelin levels were elevated in women with preeclampsia as compared with those of gestation-matched pregnant and nonpregnant controls (22.6 +/- 2.0 vs 12.0 +/- 1.0 vs 10.4 +/- 1.3 pmol/L, p less than 0.005, preeclampsia vs controls) and also were increased in late gestation (17.7 +/- 2.0 pmol/L). Endothelin correlated positively with plasma levels of uric acid (r = 0.698, p less than 0.005) and inversely with creatinine clearance (r = -0.659, p less than 0.05). CONCLUSION: Circulating endothelin levels are elevated in women with preeclampsia and correlate closely with serum uric acid levels and measures of renal dysfunction. These observations suggest that endothelin may contribute to renal vasoconstriction in preeclampsia.     

A comparative study of serum soluble vascular cell adhesion molecule-1 and soluble intercellular adhesion molecule-1 in preeclampsia.

OBJECTIVES: Maternal serum soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1) were evaluated in preeclampsia to investigate whether these molecules could be helpful with regard to this pregnancy complication. STUDY DESIGN: The study population was composed of 30 preeclamptic patients with a mean gestational age of 35.5 +/- 4.6 weeks and 20 age-matched and gestational age-matched normotensive uncomplicated pregnancies (controls). Blood samples from 7 of the 30 preeclamptic patients and 15 of the 20 controls in the second trimester were also analyzed. Data were analyzed by parametric methods. RESULTS: Significantly higher maternal serum sVCAM-1 levels were found in both groups of preeclamptic patients with and without fetal growth restriction (981 +/- 145 ng/ml; n = 13; p < 0.0005 and 846 +/- 84 ng/ml; p < 0.02, respectively) compared with controls (668 +/- 186 ng/ml). In contrast, no significant difference was found in maternal serum sICAM-1 levels between preeclamptic and normotensive pregnancies, or in both adhesion molecules (1) in the controls between second and third trimester samples and (2) in the second trimester between pregnant women who developed preeclampsia later and gestational age-matched controls. CONCLUSION: These findings show a selective significant elevation of maternal serum sVCAM-1 in preeclampsia, with the highest values in cases complicated with fetal growth restriction, perhaps reflecting its angiogenic function. Hence, sVCAM-1 could be helpful in the diagnosis of this fetal complication in preeclampsia.     

Neurokinin B peptide serum levels are higher in normotensive pregnant women than in preeclamptic pregnant women

OBJECTIVES: The purpose of this study was to examine neurokinin B levels in serum from preeclamptic and normotensive and to investigate the role of neurokinin B in preeclampsia. STUDY DESIGN: Peripheral and uterine venous blood neurokinin B levels were measured in 14 normotensive and 8 preeclamptic pregnant women by radioimmunoassay. RESULTS: Neurokinin B levels in normotensive women were 4.91 +/- 2.67 nmol/L in peripheral and 5.59 +/- 2.06 nmol/L in uterine blood. In pregnant women with preeclampsia, neurokinin B levels were 2.79 +/- 1.68 nmol/L and 3.20 +/- 1.55 nmol/L, respectively. Neurokinin B levels were significantly higher in normotensive women (P=.032 in peripheral and P=.006 in uterine blood). CONCLUSIONS: Neurokinin B serum levels were higher in normotensive women. Higher neurokinin B concentrations in normotensive pregnant women may be due to the advanced gestational age and/or the result of a negative interaction of other vasoactive substances. The role of neurokinin B in preeclampsia remains to be determined.     

Elevated amniotic fluid leptin levels in pregnant women who are destined to develop preeclampsia

OBJECTIVE: To analyze whether leptin levels of the amniotic fluid elevate during early pregnancy in women destined to develop preeclampsia and to evaluate the relationship between amniotic fluid leptin levels and gestational age, maternal body mass index, and fetal sex. STUDY DESIGN: Leptin levels of the amniotic fluid were compared in two groups of women, preeclamptic (n = 20) and normotensive pregnant (n = 40), matched for fetal sex, maternal body mass index at sampling, gravidity and fetal gestational age at sampling. Furthermore, amniotic leptin levels in 400 normotensive pregnant women were analyzed for their correlation with gestational age, maternal body mass index, and fetal sex. RESULTS: Median leptin concentrations were significantly higher (p < 0.001) in the women with preeclampsia (7.3+/-0.7 ng/ml) than in the normotensive pregnant women (4.1 +/- 0.3 ng/ml), independent of fetal sex. The leptin levels in the amniotic fluid decreased with advanced gestational age (r = 0.24, p < 0.001). Amniotic fluid leptin levels in the pregnant women carrying a female fetus (5.6+/-0.3ng/ml) were significantly higher than those carrying a male fetus (4.7+/-0.2 ng/ml) (p = 0.004). CONCLUSION: Higher amniotic fluid leptin levels were observed in the preeclamptic pregnant women, and they decreased as gestational age advanced. Furthermore, the women with a female fetus were noted to have higher amniotic fluid leptin levels.     

Cerebrospinal fluid leptin levels in preeclampsia: relation to maternal serum leptin levels

BACKGROUND: To determine whether cerebrospinal fluid (CSF) and circulating levels of leptin differ between women with preeclampsia and women who had an uncomplicated pregnancy. METHODS: Maternal serum and CSF leptin concentrations obtained in the third trimester of the gestation were compared in 16 women with mild preeclampsia and 23 normotensive pregnant women who underwent cesarean section. Before administering local anesthetic for spinal anesthesia, 2 mL CSF and 4 mL venous blood sample were taken and were stored at -30 degrees C until serum and CSF leptin levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Mean CSF leptin concentrations were not significantly different between the two groups (preeclampsia 9.7 +/- 4.2 ng/mL, normotensive 13.6 +/- 4.3 ng/mL, p = 0.952). Similarly, mean serum leptin concentrations were similar between the two groups (mild preeclampsia 21.7 +/- 7.1 ng/mL, normotensive 18.3 +/- 6.7 ng/mL, p = 0.698). CSF leptin levels are inversely related to the serum leptin concentrations in preeclamptic patients (r = -0.87, p = 0.000). An inverse relationship was also detected between CSF and serum leptin levels in normotensive pregnant subjects (r = -0.66, p = 0.000). CONCLUSIONS: CSF and serum leptin levels were similar in patients with preeclampsia and normotensive pregnant women. However, the CSF leptin was negatively correlated with the serum leptin concentrations in preeclamptic and normotensive control subjects, suggesting that leptin enters the brain by a saturable transport system. Further work is needed to confirm our findings.     

Twin pregnancy and preeclampsia

INTRODUCTION: Preeclampsia is a pregnancy-specific disorder of humans which rates among one of the major cases of maternal and fetal morbidity and mortality. Etiology of preeclampsia is still largely unraveled and treatment is syndrome specific. OBJECTIVE: Evaluation of the incidence of preeclampsia in twin pregnancies and comparison of selected clinical characteristics among preeclamptic and non-preeclamptic twin pregnancy patients. METHODS: Retrospective analysis of 194 normotensive and 25 preeclamptic patients with twin pregnancies admitted to the Lublin State Hospital Nr 4 between January 1st 1992 and December 31st 1997. Patients were matched for gravidity, parity, maternal age and selected biochemical parameters. RESULTS: Preeclampsia occurred two times more frequently in nulliparous women (68% vs 32%). Gravidas with preeclampsia had significantly higher serum uric acid levels than their non-preeclamptic counterparts (6.7 +/- 0.3 vs 4.3 +/- 0.1; p < 0.001). Hypertension, proteinuria and edema coexisted concomitantly in 52% of preeclamptic patients. CONCLUSIONS: 1. Preeclampsia complicates one tenth of twin pregnancies. 2. In preeclamptic women nulliparas were two times more frequent. 3. In preeclamptic women is significantly higher level of uric acid.     

Evaluation of maternal and umbilical serum TNFalpha levels in preeclamptic pregnancies in the intrauterine normal and growth-restricted fetus.

OBJECTIVE: The aim of this study was to carry out a comparative analysis of the maternal and umbilical cord TNFalpha serum levels in pregnancies complicated by severe preeclampsia with normal intrauterine fetal growth, in preeclamptic pregnancies with intrauterine growth restriction (IUGR), and in normotensive pregnant patients. PATIENTS AND METHODS: The study was carried out on eight patients with severe preeclampsia complicated by IUGR and 18 preeclamptic patients with normal intrauterine fetal growth. The control group consisted of 18 healthy normotensive patients with singleton uncomplicated pregnancies. Maternal and umbilical serum TNFalpha concentrations were estimated using a sandwich ELISA assay. RESULTS AND CONCLUSIONS: Pregnant women with severe preeclampsia had significantly higher maternal and umbilical serum TNFalpha levels than those in the normotensive controls. Our findings and other reports indicate that TNFalpha may participate in the pathogenesis and sequelae of preeclampsia with and without IUGR. The results of excessive umbilical serum activity of tumor necrosis factor alpha (TNFalpha) in preeclamptic pregnancy complicated by intrauterine growth restriction (IUGR) may suggest additional changes and dysfunction of the placental-fetal unit and deterioration of placental function, leading to fetal hypotrophia in the course of preeclampsia.     

Plasma and placental levels of interleukin-10, transforming growth factor-beta1, and epithelial-cadherin in preeclampsia

OBJECTIVE: To investigate the plasma and placental levels of interleukin-10 (IL-10), transforming growth factor-beta1 (TGF-beta1), and epithelial-cadherin (E-cadherin) in normotensive and preeclamptic pregnancies. METHODS: The study population consisted of 33 women with normotensive pregnancy and 35 women with preeclampsia. Peripheral venous blood samples were collected before labor (35.3 +/- 1.1 and 34.2 +/- 3.4 weeks' gestation for normotensive and preeclamptic pregnancies, respectively), and placental tissues were obtained after delivery. Maternal plasma and placental homogenate IL-10, TGF-beta1, and E-cadherin levels were determined by enzyme-linked immunosorbent assay. RESULTS: The mean plasma and placental levels of IL-10, TGF-beta1, and E-cadherin were significantly higher in preeclamptic than normotensive patients (P <.001). The plasma and placental levels of IL-10, TGF-beta1, and E-cadherin significantly increased with the increments in diastolic blood pressure (P <.001). CONCLUSION: IL-10, TGF-beta1, and E-cadherin may be involved in the pathologic process of preeclampsia. The pathophysiologic changes associated with preeclampsia may stem in part from the overproduction of these placental mediators.     

Oxidized and free whole blood thiols in preeclampsia

OBJECTIVE: To measure levels of oxidized and free thiols in whole blood of normotensive pregnant and preeclamptic women and evaluate the role of oxidative stress. METHODS: We measured whole blood oxidized and free levels of cysteine, homocysteine, cysteinylglycine, and glutathione by high performance liquid chromatography in women with normotensive pregnancies (n = 50), preeclampsia (n = 29), and preeclampsia complicated by the hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome (n = 16). RESULTS: Oxidized and free levels (median [range], micromol/L) of cysteine and homocysteine were higher in women with preeclampsia than normotensive pregnancies (45 [27-81] versus 29 [9-91], P <.001, and 98 [57-193] versus 69 [33-215], P <.001; 0.8 [0.2-4.4] versus 0.4 [0.01-1.6], P <.001, and 2.1 [0.7-9.4] versus 1.2 [0.2-21.2], P <.01; respectively). The ratios of free to oxidized cysteine, homocysteine, and cysteinylglycine were lower in preeclampsia than normotensive pregnancy (2.2 [1.3-3.0] versus 2.4 [1.7-4.3], P <.001; 2.3 [0.5-5.4] versus 2.9 [1.1-24], P <.001; 4.1 [2.3-11.6] versus 5.4 [2.6-24.3], P <.02, respectively), indicating a shift in favor of the oxidized form of those thiols. In HELLP syndrome, levels of oxidized and free cysteine and levels of oxidized homocysteine were higher than normal (44 [33-63] versus 29 [9-91], P <.001, and 102 [82-133] versus 69 [33-215], P <.001; 1.0 [0.3-2.9] versus 0.4 [0.01-1.6], P <.001, respectively). No significant differences were found in oxidized glutathione levels in women with preeclampsia (22 [5-49] versus 17 [2- 60], P =.06) or free levels in preeclamptic women with HELLP syndrome (757 [624-993] versus 842 [539-1516], P =.09) as compared with normotensive pregnant women. The ratios of free to oxidized cysteinylglycine and glutathione were higher in women with HELLP syndrome than in those with preeclampsia (5.4 [3.3-12.7] versus 4.1 [2.3-11.6], P =.02, and 56 [28-124] versus 45 [16-166], P =.02, respectively). CONCLUSION: Significantly lower ratios of free to oxidized cysteine, homocysteine, and cysteinylglycine in preeclampsia might indicate oxidative stress.     

Calciuria and preeclampsia: a case-control study

OBJECTIVE: The aim of this study was to compare calciuria of preeclamptic cases to normotensive controls among pregnant women hospitalized in the French West Indies obstetrics department. STUDY DESIGN: This case-control study included 47 preeclamptic women and 50 controls. The main outcome was 24h urinary calcium excretion rate. Serum levels of creatinine, calcium and uric acid were also analyzed. A logistic regression analysis has been performed to investigate the relationship between hypocalciuria and preeclampsia after having taken into account prognostic preeclampsia factors and pertinent clinical criteria. RESULTS: Women with preeclampsia had significantly lower calciuria than normotensive patients (1.5 mmol/24h+/-1.0 versus 6.0 mmol/24h+/-4.2, p=0.0001). After taking into account gestational age at hospitalization, body mass index and nulliparity, hypocalciuria was significantly associated with preeclampsia (ORa=21.74; 95% CI, 6.9-66.7). The diagnosis value of a calciuria less than 2.1 mmol/24h is interesting because of its negative predictive value (97%), but its positive predictive value is weak (42%). CONCLUSION: In our population, preeclamptic women had a calciuria significantly lower than controls.     

Maternal serum nitric oxide levels associated with biochemical and clinical parameters in hypertension in pregnancy

OBJECTIVES: To measure maternal serum concentrations of total nitrites, as an index of nitric oxide synthesis, in normal and hypertensive pregnant women, and to examine the correlation between these concentrations and several variables of clinical interest. STUDY DESIGN: A total of 60 women in four different groups were studied: 10 normotensive pregnant women, 17 pregnant women with preeclampsia, 18 pregnant women with gestational hypertension and 15 pregnant women with chronic hypertension. Serum nitrite levels were determined using the Griess reaction after reduction with nitrate reductase. RESULTS: Serum nitrite levels were higher in preeclamptic women (34.11+/-14 micromol/l, P=0.04), lower in chronic hypertensive women (19.56+/-6.46 micromol/l, P=0.04) and similar in women with gestational hypertension (26.97+/-9.44 micromol/l) in comparison to the control group (25.37+/-7.24 micromol/l). Serum nitrite levels in preeclamptic women had significant positive correlations with hematocrit, fasting insulinemia, and apolipoprotein B and negative correlations with platelet count, serum phosphorus and glucose:insulin ratio. In pregnant women with chronic hypertension a negative correlation was found between serum nitrite levels and active partial thromboplastin time. In pregnant women with gestational hypertension, serum nitrite levels had negative correlations with birthweight and 24-h urine calcium, and positive correlations with mean corspuscular hemoglobin, 24-h urine sodium and maternal age. CONCLUSIONS: We suggest that in women with preeclampsia, a higher maternal nitric oxide level may act as a compensatory mechanism against hemoconcentration and platelet aggregation and that nitric oxide production may be related to some metabolic events. In women with gestational hypertension, higher serum nitrite levels may be related to clinical and biochemical findings common in preeclampsia. In chronic hypertension, a lower maternal nitric oxide level is related to the status of coagulation.     

Ophthalmic artery velocimetry in normotensive and preeclamptic women with or without photophobia.

OBJECTIVE: To compare ophthalmic arterial velocimetry in normotensive and preeclamptic gravidas with and without photophobia. METHODS: Ophthalmic arteries were studied by color-flow Doppler ultrasonography in 118 normotensive pregnant women, 20 gravidas with preeclampsia and no visual symptoms, and 11 with preeclampsia, photophobia, and retinal edema. RESULTS: The ophthalmic arterial pulsatility index (PI) correlated negatively with gestational age (y = -0.01x + 1.84, r = -0.41, P<.01). Pulsatility index in preeclamptics with photophobia (0.71+/-0.17) was lowest among the three groups (P<.01) and was highest in normotensive pregnant women (1.41+/-0.21, P<.01). Mean velocity in normotensive pregnant women (0.19+/-0.05 m/second) was highest among the groups (P<.01) and was not significantly different in preeclamptic women with no visual symptoms (0.27+/-0.03 m/second) and with photophobia (0.30+/-0.02 m/second). CONCLUSION: Preeclamptic women, especially those with photophobia, have orbital vascular vasodilation or hyperperfusion, or both.     

Plasma, urinary, and salivary 8-epi-prostaglandin f2alpha levels in normotensive and preeclamptic pregnancies

OBJECTIVE: Our purpose was to measure and compare plasma, urinary, and salivary concentrations of 8-epi-prostaglandin F(2alpha) (8-isoprostane) in women with normotensive pregnancies and the respective concentrations in pregnancies complicated by preeclampsia. STUDY DESIGN: Plasma, urinary, and salivary 8-isoprostane levels were measured in pregnant women with preeclampsia (n = 40), normotensive pregnant women (n = 20), and nonpregnant women (n = 10). One-way analysis of variance was used to determine significant differences. RESULTS: Plasma free 8-isoprostane concentrations were increased in women with severe preeclampsia (342 +/- 50 pg/mL), in comparison with nonpregnant women (129 +/- 17 pg/mL) and normotensive pregnant women (150 +/- 11 pg/mL; P =.003, and.0001, respectively). Urinary excretion of 8-isoprostane was slightly but not significantly decreased in preeclampsia (1200 +/- 227 pg/mL), in comparison with urinary excretion in nonpregnant women (1625 +/- 364 pg/mL) and normotensive pregnant women (2149 +/- 432 pg/mL). Salivary concentrations of 8-isoprostane were increased in normotensive women (496 +/- 113 pg/mL), in comparison with nonpregnant women (150 +/- 27 pg/mL) but were not related to preeclampsia (419 +/- 96 pg/mL; P 相似文献   

Estimation of oxidative products of nitric oxide (nitrates, nitrites) in preeclampsia

Oxidative products of nitric oxide, serum nitrates and nitrites were estimated in 50 primigravidas with preeclampsia and in 50 gestation and age-matched normotensive primigravidas. Thirty three (66%) of these women had mild preeclampsia and 17 (34%) had severe preeclampsia. Serum nitrate and nitrite levels were significantly higher in preeclamptic women (nitrates - 15 +/- 1.17; nitrites - 11.82 +/- 1.16 micromol/L) than in the normotensive pregnant women (nitrates 11.82 +/- 1.16; nitrites - 5.08 +/- 0.47 micromol/L, p < 0.001). In preeclamptic women, serum nitrate and nitrite levels correlated with the severity of the disease (mild preeclampsia nitrate - 14.46 +/- 1.98; nitrite 6.21 +/- 0.84 micromol/L, severe preeclampsia nitrate - 16.65 +/- 3.64; Nitrite - 6.87 +/- 1.56 micromol/L). In preeclampsia there was significant positive correlation between nitrate and nitrite levels and diastolic blood pressure and proteinuria.     

Maternal and umbilical sTNF-R1 in preeclamptic pregnancies with intrauterine normal and growth retarded fetus.

OBJECTIVE: The aim of this study was to determine the maternal and umbilical cord sTNF R1 serum levels in pregnancies complicated by severe preeclampsia with normal intrauterine fetal growth and in preeclamptic pregnancies with intrauterine growth retardation (IUGR). PATIENTS AND METHODS: The study was carried out on 8 patients with preeclampsia complicated by intrauterine growth retardation (group PI) and 18 preeclamptic patients with appropriate-for-gestational-age weight infants (group P). The control group consisted of 18 healthy normotensive delivering patients with singleton uncomplicated pregnancies (group C). Maternal and umbilical serum sTNF-R1 concentrations were estimated using a sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS AND CONCLUSIONS: Pregnant women with severe preeclampsia had higher maternal and umbilical serum sTNF-R1 levels than did normotensive controls. Furthermore significantly higher umbilical levels of sTNF-R1 were observed in the group of patients with preeclampisa complicated by IUGR, compared with preeclamptic patients with appropriate-for-gestational-age weight infants. The umbilical sTNF-R1 levels in preeclamptic groups tended to be higher in comparison with the maternal levels. Our results and those of other reports seem to suggest that TNFalpha and sTNFR1 play a crucial role in pathogenesis and sequelae of preeclampsia with and without intrauterine growth retardation.     

Plasma volume determination in normal and preeclamptic pregnancies

To determine the clinical usefulness of plasma volume determinations, we measured plasma volume serially throughout pregnancy with the use of the Evans blue dye-dilution technique in 20 subjects with normal pregnancies. In comparison, four preeclamptic subjects were studied. In preeclamptic subjects compared to normal subjects, plasma volume was reduced (1763 +/- 216 versus 2345 +/- 198 ml/m2, p less than 0.001). Two normotensive subjects who subsequently developed preeclampsia had reduced plasma volumes prior to the onset of hypertension as compared to volumes in those who remained normotensive (1918 +/- 86 versus 2345 +/- 198 ml/m2, p less than 0.01). Those subjects who were delivered of infants who were small for gestational age had significantly reduced plasma volumes compared to volumes of those who were delivered of infants who were appropriate for gestational age (1950 +/- 333 versus 2237 +/- 259 ml/m2, p less than 0.05), but this was true only among gravid women with pregnancies complicated by preeclampsia. We conclude that failure of plasma volume expansion is associated with the development of preeclampsia and also intrauterine fetal growth retardation in preeclamptic subjects.     

Platelet aggregation and TGF-beta(1) plasma levels in pregnant women with preeclampsia

OBJECTIVES: Platelets and transforming growth factor-beta(1) (TGF-beta(1)) are thought to be involved in the pathogenesis of preeclampsia. Our objectives were to determine plasma concentration of TGF-beta(1) in normotensive and preeclamptic women in the third trimester of pregnancy and to evaluate the correlation of TGF-beta(1) plasma levels with platelet count and agonist-induced aggregation capacity. METHODS: Thirty-three women with preeclampsia were compared with 36 healthy women with uncomplicated pregnancies. Peripheral venous blood samples were obtained, and TGF-beta(1) plasma levels measured by an enzyme-linked immunoassay. Platelet aggregation was induced by the agonist agents adenosine diphosphate (ADP), collagen and epinephrine, and was determined in platelet-rich plasma by aggregometry. RESULTS: Plasma concentrations of active TGF-beta(1) were significantly higher in preeclamptic women (10.41+/-2.07ng/mL) compared with normotensive pregnant women (7.01+/-3.29ng/mL). Platelet number and platelet agonist-induced aggregation percent were significantly lower in patients with preeclampsia than in healthy pregnant women. A significant correlation was observed between TGF-beta(1) plasma levels and platelet agonist-induced aggregation percent as between plasma levels of TGF-beta(1) and platelet number in preeclamptic patients. CONCLUSION: The association between impairment in platelet responsiveness and higher levels of TGF-beta(1) in the plasma of patients with preeclampsia suggests that this cytokine may play a role in the pathophysiological events of preeclampsia that are dependent on platelet activation.     

Plasma thiol status in preeclampsia

OBJECTIVE: To measure plasma thiol levels in women with normal pregnancies, women with preeclampsia, and nonpregnant controls to define plasma thiol's effect on glutathione homeostasis and pathophysiology of preeclampsia. METHODS: Total plasma cysteine, gamma-glutamylcysteine, homocysteine, cysteinylglycine, and glutathione levels were measured in ten nonpregnant women, ten women with normotensive pregnancies, and 20 women with preeclampsia at delivery. RESULTS: Median total plasma levels of all thiols in normotensive pregnant women were significantly lower than in nonpregnant women. Median total plasma cysteine and homocysteine levels in women with preeclampsia were significantly higher compared with pregnant controls (254 versus 190 micromol/L, P < .001; and 13.3 versus 8.4 micromol/L, P < .02, respectively), whereas glutathione levels were significantly lower in women with preeclampsia compared with those in pregnant controls (5.1 versus 6.3 micromol/L, P < .05). CONCLUSION: In women with preeclampsia, homocysteine and cysteine levels, which are lowered in normotensive pregnancy, were comparable to levels in nonpregnant women, whereas glutathione levels were lower. Those results suggest that in women with preeclampsia, glutathione use is higher or its synthesis is disturbed. Therefore, glutathione might affect pathophysiology of preeclampsia.