S226

5 3 2

SMFM Abstracts

LABOR DEPLETES VITAMIN C IN THE MOTHER AND FETUS BUT MAIN- TAINS VITAMIN E JAMES WOODS ~, JUDITH CAVANAUGH t, MARK PLESSINGER 1, EDWARD NORKUS 2, RICHARD M1LLERI; ]University of Rochestel; Rochestex, NY: '~Our Lady of Mercy Medical Centex, Bronx, NY

OBJECTIVE: We have previously reported in five healthy women (Placenta, 2001) that following uncmnplicated vaginal delivery (VD) at term, maternal plasma vitamin E > fetal (cord) plasma, while aumiotic fluid vitamin C > fetal plasma > maternal plasma. It is not known if labor alters vitamins C and E in the maternal-fetal compartments. We cmnpared our reported levels of vitamins C and E in laboring subjects with subjects of similar dietary intake undergoing elective repeat cesarean section (CS) without labor.

STUDY DESIGN: Five healthy women undergoing elective repeat cesarean section at term (>38 weeks' gestation) were studied. Maternal and fetal (cord) blood, amniotic fluid, and chorioamnion samples were collected at time of surgery. Each subject completed a detailed nutritional questionnaire. Plasma vitamin E was determined by HPLC and standardized to cholesterol. Vitamin C was de termined using the 2,4-DNPH method. Membrane vitamin E was measured by reversed-phase HPLC and standardized to membrane protein.

RESULTS: Dietary intakes for vitamins C and E were the same in both groups. Results are mean+/-SD.

CONCLUSION: Laboring patients have signifcantly lower levels of vitamin C in maternal plasma, amniotic fluid and cord plasma than repeat cesarean section patients. In contrast, vitamin E levels in botll groups are similar. From these data we speculate that labor generates reactive oxygen species and that vitamin C is depleted as it recycles vitamin E. Supported in part by HD38971.

Figure

Mat Plasma Ar~t ~ C¢~'d P~asma Chork~rnn]o~

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534

December 2001 AmJ Obstet Gynecol

CYCLIC GUANOSINE 3",5"-MONOPHOSPHATE (CGMP) IS ASSOCIATED WITH APOPTOSIS IN PATIENTS WITH INTRA-AMNIOTIC INFECTION CHAUR-DONG HSUL JIANN-HWA WANGL KIRSTEN AVERSA 2, HASSAN HARIRAH3; 1University of Nebraska Medical Center, Obstetrics or Gyne- cology, Omaha, NE; Wale University, Obstetrics or Gynecology, New Haven, CT; 3University of Texas Medical Branch at Galveston, Obstetrics and Gynecology, Galveston, TX

OBJECTIVE: The aim of this study was I t investigate whether cGMP was associated with apoptosis in the pathogenesis of intra-amniotic infection (IAI). We determined amuiotic fluid (AF) levels of cGMP, soluble Fas (sFas), and soluble Fas ligand (sFasL) in patients with and without intra-amniotic infection

STUDY DESIGN: Forty-two singleton pregnant women were studied. Twenty-one patients were with IAI and 21 patients were not. IAI was defined as the presence of a positive AF culture. AF was tested for Gram stain, glucose, leukocytes, cGMP, sFas, and sFasL. AF levels of cGMP, sFas, and sFasL were determined by enzyme immunoassay. Statistical analyses were performed using two-tailed t test, linear regression and correlation tests. Data were expressed as mean _+ SEM.

RESULTS: There were no significant differences in maternal age, gestational age, parity, and race between patients with and without IAI. AF mean levels of cGMP, sFas, and sFasL were significantly higher in patients with IAI than in those without IAI (cGMP: 18.92 + 1.72 vs 11.17 _+ 0.94 nmol/L, P< .001 and sFas: 4.99 + 0.81 vs 1.97 -+ 0.34 U / m L P= .001; and sFasL: 0.44 + 0.06 vs 0.22 + 0.02 ng /mL, P< .001). AF levels of cGMP were significantly correlated with AF sFas, and sFaL (cGMP/sFas: r = 0.48, P = .001, and cGMP/sFasL: r = 0.49, P= .001). AF sFas and sFasL levels were also significantly correlated (r - 0.80, P < .0001 ). Patients with IA1 had significantly higher AF leukocyte counts and significantly lower glucose levels than those without IA1. AF cGMP, sFas, and sFasL were all positively correlated with AF leukocytes and negatively correlated with AF glucose levels.

CONCLUSION: Significantly elevated and correlated AF cGMP with AF sFas and sFasL suggests that cGMP is associated with apoptosis signal pathway in patients with IAI.

533 PHENOTYPIC EXPRESSION IN MURINE SKELETAL MUSCLE: THE IM- PACT OF A TISSUE SPECIFIC CONDITIONAL KNOCK-OUr OF HIF-lc~ MATTHEW KIM 1, RICHARD HOWLETT 2, THOMAS MOORE 1, PETER WAGNER 2, RANDALL JOHNSON3; 1University of California, San Diego, Reproductive Medicine, San Diego, CA; '-'University of California, San Diego, Medicine, La Jolla, CA; 3University of Calitornia, San Diego, Biology, La Jolla, CA

OBJECTIVE: To evaluate tile phenotypic impact of knocking out hypoxia inducible fb_ctor lct (HIF-lct) expression in skeletal muscle by utilizing Cre- loxP recombination with a muscle creatine kinase (MCK) promoter in the mouse. We hypothesized that the knock out transgenic mouse (KO) would demonstrate decreased muscle function compared to wild-type (WT) controls.

STUDY DESIGN: 6 KO were compared to 6 WT littermates using a standard protocol for isolated muscle stimulation. Fatigued muscle as well as contralateral unstimulated muscle were immediately collected and quick frozen in liquid nitrogen for analysis. Tissues were analyzed for ATE lactate and phosphocreatine through enzymatic spectrophotometry. Histologic analysis was performed with CD-3I antibody for vascular endothelium and PAS stain for glycogen stores.

RESULTS: KO demonstrated siguificantly more rapid loss of force with stimulation compared to WT. In spite of the more rapid loss of function, KO had lower lactate (P< .004) and higher phosphocreatine (P< .04). ATP levels were not statistically different. Histologically KO had significantly less dense vascularization but greater stores of glycogen.

CONCLUSION: Relatively little is known regarding the mechanisms of adaptation to hypoxia at the molecular level during pregnancy. A mechanistic understanding of these processes both in terms of fetal adaptation and maternal physiology are critical to a better understanding of both normal and complicated pregnancies. The present study is the first to demonstrate the role of HIF-lc~ in muscle function. HIF-I~ is the primary transcriptional regulatory factor for hypoxic response, controlling expression of VEGF, erythropoietin, glucose transporters and glycolytic enzymes. These findings suggest that HIF- 10~ has a further role in energy metabolism and acute function in skeletal muscle most likely related to fatigue or bypoxia signaling. Further studies in smooth muscle and in particular tile uterus are planned.

535 NON-INVASIVE ULTRASOUND ASSESSMENT OF VASCUIAR REACTIV- ITY IN NORMAL PREGNANCIES USING MATERNAL BRACHIAL ARTERY DIAMETER WENDY KINZLER 1 , JOHN SMULIAN 1, CANDE ANANTH 1, AN- THONY VINTZILEOS 1, 1UMDNJ-Robert Wood Johnson Medical School/ Saint Peter's University Hospital, Obstetrics, Gynecology and Reproductive Sciences, New Brunswick, NJ

OBJECTIVE: To define patterns of vascular reactivity in normal preg- nancies by post-occlusion brachial artery diameter (BAD).

STUDY DESIGN: This was a longitudinal study of singleton pregnancies. Women with multiple gestations, chronic hypertension, diabetes, vascular disease or pregnancy-induced hypertension in the past or present preguancy were excluded. A blood pressure cuff on the proximal arm was inflated to achieve brachial artery blood flow occlusion tot 5 minutes. End-diastolic BAD was measured pre-occlusion and at 1, 3 and 5 minutes post-occlusion in each trimester using a 12-5 MHz transducer. The % change in BAD compared to baseline was calculated. Longitudinal data was analyzed based using models based on generalized estimating equations, controlling for body mass index, tobacco, caffeine, prenatal vitamin use and high fat meal intake.

RESULTS: The mean maternal age _+ standard deviation was 26.4 -+ 6.2 years. Mean baseline BADs (cm) _+ standard error (SE) for 1st, 2nd and 3rd trimesters were 0.28 -+ 0.01, 0.29 -+ 0.01 and 0.31 _+ 0.01, respectively. BADs were greater than baseline at all post-occlusion times (P< .0001) in every trimester. There were no significant differences in % diameter change between the 1st and 2nd trimesters. One and 3 minute post-occlusion % diameter changes were significantly lower in the 3rd trimester compared with the 1st trimester.

CONCLUSION: BAD significantly increases in response to a transient ischemic stress. This increase is most marked at I minute post-occlusion, regardless of trimester. However, the ability of the brachial a r t e~ to dilate is significantly less in the 3rd trimester. This establishes normative data on endothelium~lependent vascular responses throughout normal pregnancy.

Table Mean % diameter changes (-+SE)

1ST TRI (N = 42) 2 ND TRI (N = 23) 3RD TRI (N = 22)

1 Min 19.1 _+ 1.3% 18.8 -+ 1.4% 15.1 _+ 1.6% 3 Min 16.2 + 1.4% 13.0 _+ 1.6% 7.7 _+ 1.7% 5 Min 8.7 + 2.9% 7.8 -- 1.5% 5.5 _+ 1.4%