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Ovári L, Aranyosi J, Balla G. Acute effect of cigarette smoking on placental circulation - a study by carbon-monoxide measurement and Doppler assessment. ACTA ACUST UNITED AC 2009; 96:243-50. [PMID: 19457768 DOI: 10.1556/aphysiol.96.2009.2.9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Carbon-monoxide (CO) decreases placental vascular impedance. We assessed the consequences of smoking-induced temporary maternal CO-increase on fetal and placental circulation. STUDY DESIGN In a prospective study twenty-nine smoking pregnant women and their fetuses were evaluated. We determined the changes in maternal blood CO levels after smoking, and the concomitant changes in maternal and fetal circulation. Changes in fetal heart rate, uterine artery (UTA), middle cerebral artery (MCA), and descending aorta (DA) flow were measured by Doppler velocimetry. Changes in maternal CO level and umbilical flow value were assessed by paired t-test. The correlation between CO level and placental flow was assessed by partial correlation test. RESULTS CO level increased (mean +/-SD 1.7 +/- 0.065% vs. 2.36 +/- 0.89, p<0.0001). Nicotine-related maternal circulatory parameters changed significantly, but uterine flow values remained unchanged. Fetal heart rate increased, while flow in MCA and DA showed no change. CO-dependent umbilical artery impedance remained unchanged (Pulsatility Index: 0.956 +/- 0.18 vs. 0.948 +/- 0.21). Partial correlation between CO level and umbilical arterial impedance showed no significance (r:-0.324). CONCLUSION Despite significant CO elevation, the mainly CO-regulated placental flow remained unchanged.
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Maharaj CH, O'Toole D, Lynch T, Carney J, Jarman J, Higgins BD, Morrison JJ, Laffey JG. Effects and mechanisms of action of sildenafil citrate in human chorionic arteries. Reprod Biol Endocrinol 2009; 7:34. [PMID: 19389232 PMCID: PMC2680410 DOI: 10.1186/1477-7827-7-34] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Accepted: 04/23/2009] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES Sildenafil citrate, a specific phosphodiesterase-5 inhibitor, is increasingly used for pulmonary hypertension in pregnancy. Sildenafil is also emerging as a potential candidate for the treatment of intra-uterine growth retardation and for premature labor. Its effects in the feto-placental circulation are not known. Our objectives were to determine whether phosphodiesterase-5 is present in the human feto-placental circulation, and to characterize the effects and mechanisms of action of sildenafil citrate in this circulation. STUDY DESIGN Ex vivo human chorionic plate arterial rings were used in all experiments. The presence of phosphodiesterase-5 in the feto-placental circulation was determined by western blotting and immunohistochemical staining. In a subsequent series of pharmacologic studies, the effects of sildenafil citrate in pre-constricted chorionic plate arterial rings were determined. Additional studies examined the role of cGMP and nitric oxide in mediating the effects of sildenafil. RESULTS Phosphodiesterase-5 mRNA and protein was demonstrated in human chorionic plate arteries. Immunohistochemistry demonstrated phosphodiesterase-5 within the arterial muscle layer. Sildenafil citrate produced dose dependent vasodilatation at concentrations at and greater than 10 nM. Both the direct cGMP inhibitor methylene blue and the cGMP-dependent protein kinase inhibitor Rp-8-Br-PET-cGMPS significantly attenuated the vasodilation produced by sildenafil citrate. Inhibition of NO production with L-NAME did not attenuate the vasodilator effects of sildenafil. In contrast, sildenafil citrate significantly enhanced the vasodilation produced by the NO donor sodium nitroprusside. CONCLUSION Phosphodiesterase-5 is present in the feto-placental circulation. Sildenafil citrate vasodilates the feto-placental circulation via a cGMP dependent mechanism involving increased responsiveness to NO.
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Striuk RI, Bukhonkina IM, Sokova EA, Nemirovskiĭ VB, Kosmacheva AV. [Pharmacotherapy and analysis of the course of pregnancy and perinatal outcomes in women with hypertensive disease]. KARDIOLOGIIA 2009; 49:29-32. [PMID: 20038278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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Klebanoff MA, Meis PJ, Dombrowski MP, Zhao Y, Moawad AH, Northen A, Sibai BM, Iams JD, Varner MW, Caritis SN, O'Sullivan MJ, Leveno KJ, Miodovnik M, Conway D, Wapner RJ, Carpenter M, Mercer BM, Ramin SM, Thorp JM, Peaceman AM. Salivary progesterone and estriol among pregnant women treated with 17-alpha-hydroxyprogesterone caproate or placebo. Am J Obstet Gynecol 2008; 199:506.e1-7. [PMID: 18456237 PMCID: PMC2794481 DOI: 10.1016/j.ajog.2008.03.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2007] [Revised: 12/05/2007] [Accepted: 03/03/2008] [Indexed: 11/24/2022]
Abstract
OBJECTIVE The objectives of the study was to determine whether salivary progesterone (P) or estriol (E3) concentration at 16-20 weeks' gestation predicts preterm birth or the response to 17alpha-hydroxyprogesterone caproate (17OHPC) and whether 17OHPC treatment affected the trajectory of salivary P and E3 as pregnancy progressed. STUDY DESIGN This was a secondary analysis of a clinical trial of 17OHPC to prevent preterm birth. Baseline saliva was assayed for P and E3. Weekly salivary samples were obtained from 40 women who received 17OHPC and 40 who received placebo in a multicenter randomized trial of 17OHPC to prevent recurrent preterm delivery. RESULTS Both low and high baseline saliva P and E3 were associated with a slightly increased risk of preterm birth. However, 17OHPC prevented preterm birth comparably, regardless of baseline salivary hormone concentrations. 17OHPC did not alter the trajectory of salivary P over pregnancy, but it significantly blunted the rise in salivary E3 as well as the rise in the E3/P ratio. CONCLUSION 17OHPC flattened the trajectory of E3 in the second half of pregnancy, suggesting that the drug influences the fetoplacental unit.
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Rytlewski K, Olszanecki R, Lauterbach R, Grzyb A, Kiec-Wilk B, Dembinska-Kiec A, Basta A. Effects of oral l-arginine on the pulsatility indices of umbilical artery and middle cerebral artery in preterm labor. Eur J Obstet Gynecol Reprod Biol 2008; 138:23-8. [PMID: 17719167 DOI: 10.1016/j.ejogrb.2007.06.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Revised: 05/17/2007] [Accepted: 06/14/2007] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The objective of the study was the estimation of the influence of oral supplementation with low-dose l-arginine on feto-placental circulation in women with threatened preterm labor. STUDY DESIGN Oral administration of 3g of L-arginine daily or placebo as a supplement to standard tocolytic therapy was tried in 70 women with threatened preterm delivery, randomly assigned to the L-arginine (n=37) or placebo (n=33) groups. Twenty-five and 20 completed the study, respectively. Doppler velocimetry of pulsatility indices (PI) of the umbilical (UA) and middle cerebral (MCA) arteries as well as pregnancy outcome and biochemical markers of nitric oxide synthesis (plasma amino acid and nitrite/nitrate levels, as well as 24 h nitrite/nitrate excretion with urine) were estimated. RESULTS Starting from the second week of therapy, the UA PI values were significantly lower in the L-arginine group than in the placebo group. Moreover, treatment with L-arginine caused a significant increase in MCA PI and cerebro-placental ratio (CPR) values. The changes in feto-placental circulation in the L-arginine group were not associated with any signs of increased nitric oxide synthesis. CONCLUSION Oral supplementation with low doses of L-arginine changed feto-placental blood flow distribution in patients with threatened preterm labor. The exact mechanism of L-arginine action on feto-placental circulation requires further investigation.
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Valensise H, Vasapollo B, Novelli GP, Giorgi G, Verallo P, Galante A, Arduini D. Maternal and fetal hemodynamic effects induced by nitric oxide donors and plasma volume expansion in pregnancies with gestational hypertension complicated by intrauterine growth restriction with absent end-diastolic flow in the umbilical artery. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2008; 31:55-64. [PMID: 18098350 DOI: 10.1002/uog.5234] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
OBJECTIVE To evaluate the effect of plasma volume expansion (PVE) and nitric oxide (NO) donors, in addition to antihypertensive therapy for gestational hypertensive pregnancies complicated by intrauterine growth restriction (IUGR) with absent end-diastolic flow (AEDF) in the umbilical artery (UA). METHODS This was a case-control study into which 32 gestational hypertensive pregnancies with IUGR and AEDF were enrolled. Sixteen of these were treated with antihypertensive drugs, NO donors and PVE (Group A), and 16, matched for maternal age, gestational age and fetal conditions, were treated with antihypertensive drugs only (Group B). All patients underwent fetal and uteroplacental assessment and maternal echocardiography to evaluate total vascular resistance (TVR) and cardiac output before and 5-14 days after initiation of treatment. RESULTS After 5-14 days of treatment, the maternal TVR in Group A fell from 2170 +/- 248 to 1377 +/- 110 dynes.s.cm(-5) (P < 0.01), and that in Group B fell from 2090 +/- 260 to 1824 +/- 126 dynes.s.cm(-5) (P < 0.01), with the reduction being greater in Group A than in Group B (P < 0.01). There was a significant increase in cardiac output in Group A after 5-14 days of treatment vs. baseline (6.19 +/- 0.77 vs. 4.32 +/- 0.66, P < 0.001), and, after treatment, cardiac output was significantly greater in Group A than it was in Group B (6.19 +/- 0.77 vs. 4.70 +/- 0.44, P < 0.001). Reappearance of end-diastolic flow in the UA occurred in 14/16 patients in Group A but in no patients in Group B (87.5% vs. 0%, P < 0.05). The interval between detection of UA-AEDF and delivery was 28 +/- 16 days in Group A and 11 +/- 6 days in Group B (P < 0.05). CONCLUSION Administration of NO donors and PVE in gestational hypertensive pregnancies affected by IUGR and UA-AEDF appears to improve both maternal and fetal hemodynamics, inducing prolongation of gestation.
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Milchev N, Markova D, Dimitrova E. [Use of phlebodia in pregnant women with feto-placental insufficiency (preeclampsia)]. AKUSHERSTVO I GINEKOLOGIIA 2008; 47 Suppl 1:15-17. [PMID: 18935851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Nanovskaya TN, Nekhayeva IA, Hankins GDV, Ahmed MS. Transfer of methadone across the dually perfused preterm human placental lobule. Am J Obstet Gynecol 2008; 198:126.e1-4. [PMID: 18166326 DOI: 10.1016/j.ajog.2007.06.073] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 03/15/2007] [Accepted: 06/29/2007] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The objective of the study was to determine the effect of gestational age and P-glycoprotein expression on transplacental transfer of methadone. STUDY DESIGN Dual perfusion of placental lobule was utilized. Methadone (200 ng/mL) and its [3H]-isotope were cotransfused from the maternal-to-fetal circuit with the marker compound antipyrine (20 microg/mL) and its [14C]-isotope. Concentration of the drugs in trophoblast tissue and both circuits was determined by liquid scintillation spectrometry. RESULTS Fetal transfer rate of methadone in preterm placentas was 19 +/- 5.8%, and in term placentas it was 31 +/- 9.7% (P < .01). Clearance index of methadone in preterm placentas (0.57 +/- 0.2) was lower than in term placentas (0.95 +/- 0.3, P < .01). P-glycoprotein expression was higher in preterm than term placentas. CONCLUSION The ex vivo transfer of methadone across preterm placentas is 30% lower than in term placentas.
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Mills TA, Baker PN, Wareing M. The effect of mode of delivery on placental chorionic plate vascular reactivity. Hypertens Pregnancy 2007; 26:201-10. [PMID: 17469010 DOI: 10.1080/10601330701274824] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To determine whether delivery mode influences placental chorionic plate arterial and venous vascular reactivity. METHODS Normal term placentas were obtained after vaginal delivery or cesarean section. Chorionic plate arterial and venous function was assessed by wire myography. RESULTS Sodium nitroprusside-induced arterial relaxation increased post cesarean section at 20% oxygen. Decreased U46619-induced venous contraction was observed in vaginal deliveries at 7% oxygen. Sodium nitroprusside-induced relaxation increased in vaginal delivery at 20% oxygen. CONCLUSION Delivery mode does not alter chorionic plate arterial vascular reactivity under physiological conditions, however venous reactivity was modified, a factor for consideration when interpreting functional experimental data.
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He W, Greenwell RJ, Brooks DM, Calderón-Garcidueñas L, Beall HD, Coffin JD. Arsenic exposure in pregnant mice disrupts placental vasculogenesis and causes spontaneous abortion. Toxicol Sci 2007; 99:244-53. [PMID: 17569693 DOI: 10.1093/toxsci/kfm162] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Arsenic is an abundant toxicant in ground water and soil around areas with extractive industries. Human epidemiological studies have shown that arsenic exposure is linked to developmental defects and miscarriage. The placenta is known to utilize vasculogenesis to develop its circulation. The hypothesis tested here states the following: arsenic exposure causes placental dysmorphogenesis and defective placental vasculogenesis resulting in placental insufficiency and subsequent spontaneous abortion. To test this hypothesis, pregnant mice were exposed to sodium arsenite (AsIII) through drinking water from conception through weanling stages. Neonatal assessment of birth rates, pup weights, and litter sizes in arsenic exposed and control mothers revealed that AsIII-exposed mothers had only 40% the fecundity of controls. Preterm analysis at E12.5 revealed a loss of fecundity at E12.5 from either 20 ppm or greater exposures to AsIII. There was no loss of fecundity at E7.5 suggesting that spontaneous abortion occurs during placentation. Histomorphometry on E12.5 placentae from arsenic-exposed mice revealed placental dysplasia especially in the vasculature. These results suggest that arsenic toxicity is causative for mammalian spontaneous abortion by virtue of aberrant placental vasculogenesis and placental insufficiency.
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Goyarts T, Dänicke S, Brüssow KP, Valenta H, Ueberschär KH, Tiemann U. On the transfer of the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) from sows to their fetuses during days 35–70 of gestation. Toxicol Lett 2007; 171:38-49. [PMID: 17544604 DOI: 10.1016/j.toxlet.2007.04.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Revised: 04/11/2007] [Accepted: 04/12/2007] [Indexed: 11/21/2022]
Abstract
Eleven pregnant sows with a body weight between 153 and 197 kg were fed a control diet (CON, 0.15 mg DON and 0.0035 mg ZON/kg diet) or a diet containing 15% of Fusarium toxin contaminated triticale (MYCO, 4.42 mg DON and 0.048 mg ZON/kg diet) in the period of day 35 and 70 of gestation. The indirect effect of feed intake was separated from the direct effects of the Fusarium toxins by the restricted feeding regimen where all sows were fed the same amount of feed (2000 g/d) over the whole study. At the end of experiment, fetuses were delivered by Caesarian section and samples of serum, bile, urine, liver, kidney and spleen of euthanatized sows and fetuses were taken to analyze the concentrations of DON, ZON and their metabolites. Feeding the Fusarium toxin contaminated diet to pregnant sows caused neither adverse effects on performance, organ weights and maintenance of pregnancy of sows nor on fetus weight and length. Furthermore, no teratogenic or embryolethal effects could be observed in the MYCO group. Hematological and clinical-chemical parameters of sows and fetuses were not affected by feeding, with the exception of significantly lower GLDH (glutamate dehydrogenase) serum activities in MYCO sows. The carry over of DON and ZON from the diet to the sow or fetus tissues was calculated by the diet ratio (sum of concentrations of all metabolites in the physiological specimen divided by the dietary toxin concentration), while the fetus ratio was evaluated by the sum of concentrations of all metabolites in the physiological specimen of the fetus divided by that of the sows. DON and deepoxy-DON were found in urine, bile, serum, liver, kidney and spleen of sows of the MYCO group, but not in the bile of fetuses (spleen not analyzed). ZON and its metabolite alpha-zearalenol (alpha-ZOL) were detected in urine and bile of sows, while all specimens of fetuses as well as serum and liver of sows were negative for ZON metabolites. The maximum diet ratios for urine and bile in sows of the MYCO group were 0.84 and 0.05 for DON metabolites and 1.2 and 3.8 for ZON metabolites, underscoring the differences in metabolism and excretion of both toxins. The maximum diet ratio of DON and deepoxy-DON into liver, kidney and spleen of MYCO sows were 0.003, 0.007 and 0.003, respectively. The maximum fetus ratio of DON and deepoxy-DON into urine, bile, serum, liver and kidney of fetuses were 0.006, 0, 0.5, 0.88, and 0.33, while the maximum placental ratio (sum of toxin concentrations in the physiological specimen of the fetus divided by the toxin serum concentration of the sow) were 0.64, 0, 0.50, 0.70 and 0.52, respectively. Therefore, it can be concluded that the developing fetus is exposed to DON between the gestation days 35 and 70 when the sows are fed a Fusarium toxin contaminated diet. ZON concentration in the MYCO diet was too low to get reliable results for fetus or placental ratios.
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Parry S, Zhang J. Multidrug resistance proteins affect drug transmission across the placenta. Am J Obstet Gynecol 2007; 196:476.e1-6. [PMID: 17466710 DOI: 10.1016/j.ajog.2007.02.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2006] [Revised: 02/02/2007] [Accepted: 02/20/2007] [Indexed: 11/30/2022]
Abstract
OBJECTIVE We studied the role of multidrug resistance proteins in regulating transplacental transmission of corticosteroids and protease inhibitors. STUDY DESIGN We performed quantitative polymerase chain reaction and FACS analyses to study MDR1 (encodes P-glycoprotein) and MRP-1 expression in extravillous (HTR-8/SVneo) and villous (BeWo) trophoblast cells treated with saquinavir, a multidrug resistance protein substrate. We measured H3-dexamethasone and H3-ritonavir transfer across confluent, syncytialized BeWo cells before and after treatment with agents that inhibit multidrug resistance proteins. RESULTS Compared with baseline expression, messenger RNA and protein levels were increased significantly in trophoblast cells after treatment with saquinavir. H3-dexamethasone and H3-ritonavir levels increased in BeWo cells after treatment with anti-P-glycoprotein antibodies or cyclosporine A. Transfer of H3-labeled drugs from the apical (eg, maternal) to basolateral (eg, fetal) side of the syncytialized BeWo cell monolayer was increased significantly when cells were pretreated with anti-P-glycoprotein antibodies. CONCLUSION Multidrug resistance proteins regulate drug levels in trophoblast cells and may mediate transmission of therapeutic agents across the placenta.
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Salvesen KA, Vanky E, Carlsen SM. Metformin treatment in pregnant women with polycystic ovary syndrome--is reduced complication rate mediated by changes in the uteroplacental circulation? ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2007; 29:433-7. [PMID: 17330831 DOI: 10.1002/uog.3965] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
OBJECTIVES To study a possible effect of metformin on the uteroplacental circulation. METHODS Forty pregnant women with polycystic ovary syndrome (PCOS) were enrolled in a randomized, double-blind, placebo-controlled trial of metformin (1700 mg/day) during pregnancy. Doppler ultrasound examinations of the uterine arteries were performed at 12, 19, 24, 32 and 36 gestational weeks and of the umbilical artery at 19, 24, 32 and 36 gestational weeks. RESULTS There was a greater mean bilateral uterine artery pulsatility index (PI) at 12 weeks (1.95 vs. 1.58, P = 0.02), and a greater reduction in mean PI from 12 to 19 weeks (P = 0.03) in metformin-treated women. There were no differences in mean PI values between groups at 19, 24, 32 or 36 gestational weeks. Pregnancy complications, such as preterm delivery before 32 weeks, severe pre-eclampsia or serious postpartum events, occurred only in the placebo group (7 of 22 vs. 0 of 18, P = 0.01). There were no associations between uterine artery Doppler measurements and pregnancy complications. We found no differences between groups in mean umbilical artery PI at 19, 24, 32 or 36 gestational weeks. CONCLUSIONS In this small randomized trial, metformin treatment in pregnancy reduced uterine artery impedance between 12 and 19 weeks of gestation, and this was associated with reduced complication rate. Published by John Wiley & Sons, Ltd.
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Juul SE, Aylward E, Richards T, McPherson RJ, Kuratani J, Burbacher TM. Prenatal Cord Clamping in Newborn Macaca nemestrina: A Model of Perinatal Asphyxia. Dev Neurosci 2007; 29:311-20. [PMID: 17762199 DOI: 10.1159/000105472] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Accepted: 09/08/2006] [Indexed: 11/19/2022] Open
Abstract
Our objective was to establish a nonhuman primate model of perinatal asphyxia appropriate for preclinical evaluation of neuroprotective treatment strategies under conditions that closely resemble human neonatal emergencies, and to begin testing the safety and efficacy of erythropoietin neuroprotective treatment. Prior to delivery by hysterotomy, the umbilical cords of near term Macaca nemestrina (n = 8) were clamped for times ranging between 12 and 15 min. Animals received erythropoietin (5,000 U/kg/dose x 2 i.v., n = 3), or vehicle (n = 5) after resuscitation. We assessed physiologic parameters, continuous electroencephalogram, magnetic resonance imaging/spectroscopy, safety parameters and behavior. Animals were euthanized at 4 months of age. Mean birth weight was 507 +/- 62 g. Initial arterial pH ranged from 6.75 to 7.12, with base deficits of 17-25 mEq. Animals were flaccid at birth, with attenuated electroencephalograms, and seizures occurred in 3 of 8 animals. We demonstrated magnetic resonance imaging/spectroscopy changes consistent with hypoxia (elevated lactate levels were present in some animals), significant motor and behavioral abnormalities (particularly with 15 min of cord clamping), and evidence of gliosis at the time of death. We have established a reproducible model of moderate to severe perinatal hypoxic-ischemic injury in M. nemestrina newborns. This model, which combines structural, biochemical, and behavioral assessments over time can be used to assess the safety and efficacy of neuroprotective strategies.
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Czajkowski K, Sienko J, Mogilinski M, Bros M, Szczecina R, Czajkowska A. Uteroplacental circulation in early pregnancy complicated by threatened abortion supplemented with vaginal micronized progesterone or oral dydrogesterone. Fertil Steril 2006; 87:613-8. [PMID: 17126337 DOI: 10.1016/j.fertnstert.2006.07.1506] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 07/18/2006] [Accepted: 07/18/2006] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare the influence of vaginal micronized progesterone and oral dydrogesterone supplementation on uteroplacental circulation in early pregnancy that is complicated by threatened abortion. DESIGN Randomized, parallel group, double-blind, double dummy-controlled study. SETTING Tertiary care university hospital. PATIENT(S) Fifty-three patients with threatened abortion and a living embryo. INTERVENTION(S) Three hundred milligrams of micronized vaginal progesterone or 30 mg of oral dydrogesterone daily supplementation for 6 weeks, serial transvaginal Doppler ultrasound measurement of pulsatility index, resistance index, and systolic/diastolic ratio of the spiral arteries, the uterine arteries, and the intrachorionic area. MAIN OUTCOME MEASURE(S) Uteroplacental blood flow. RESULT(S) The study demonstrated that vaginal progesterone administration, but not oral dydrogesterone treatment, results in the decrease in the spiral artery pulsatility and resistance index and systolic/diastolic ratio. Insignificant decrease in pulsatility index and resistance index of the uterine artery was observed at >9 weeks and was not associated with treatment regimen. Dydrogesterone treatment was only accompanied by the decrease in the uterine artery systolic/diastolic ratio. CONCLUSION(S) Vaginal progesterone and oral dydrogesterone supplementation have a different influence on the uteroplacental circulation in early pregnancy that is complicated by threatened abortion.
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Bainbridge SA, Belkacemi L, Dickinson M, Graham CH, Smith GN. Carbon monoxide inhibits hypoxia/reoxygenation-induced apoptosis and secondary necrosis in syncytiotrophoblast. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 169:774-83. [PMID: 16936254 PMCID: PMC1698837 DOI: 10.2353/ajpath.2006.060184] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pre-eclampsia, a hypertensive disorder of pregnancy, affects 5 to 7% of pregnancies. Oxidative stress-induced placental injury and subsequent release of placental debris into the maternal circulation are key pathogenic events in the progression of pre-eclampsia. Women who smoke cigarettes throughout pregnancy are 33% less likely to develop this disorder than nonsmoking women. We postulated that elevated carbon monoxide concentrations in serum of smoking women inhibits apoptosis and debris shedding of trophoblast cells exposed to ischemia-reperfusion injury because carbon monoxide has cytoprotective effects on endothelial and smooth muscle cells in culture. This may be responsible for the reduced risk of pre-eclampsia in smoking women. To assess the cytoprotective properties of carbon monoxide within placental tissue, carbon monoxide treatments were administered to in vitro hypoxia/reoxygenation-insulted villous explants cultured from term human placenta. Induction of apoptosis was assessed using molecular and morphological approaches. Placental villous explants treated with carbon monoxide demonstrated 60% less hypoxia/reoxygenation-induced apoptosis in the differentiated syncytiotrophoblast layer compared with untreated explants undergoing a similar insult. In addition, retention of intact syncytial membranes was observed in carbon monoxide-treated explants. These observations indicate that carbon monoxide has potent antiapoptotic properties within human placenta and may hold therapeutic potential in the treatment of pre-eclampsia.
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Riley E. Ephedrine and phenylephrine for treatment of maternal hypotension. Br J Anaesth 2006; 96:804; author reply 804-5. [PMID: 16698872 DOI: 10.1093/bja/ael089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Wareing M, Greenwood SL, Fyfe GK, Baker PN, Taggart MJ. Glibenclamide Inhibits Agonist-induced Vasoconstriction of Placental Chorionic Plate Arteries. Placenta 2006; 27:660-8. [PMID: 16026833 DOI: 10.1016/j.placenta.2005.05.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2004] [Revised: 05/16/2005] [Accepted: 05/16/2005] [Indexed: 11/26/2022]
Abstract
BACKGROUND Preliminary data suggest that K(ATP) channels may be expressed in placental arteries and veins [Wareing M, Turner C, Greenwood SL, Baker PN, Fyfe GK. Expression of mRNA encoding K+ channels in chorionic plate arteries and veins. J Soc Gynecol Investig 2004;11:353A]. However, no data exist on glibenclamide's effects in placental chorionic plate arteries. AIM To assess the effect of glibenclamide on placental chorionic plate arterial vasoconstriction. METHODS Arteries were dissected from placental chorionic plate biopsies obtained at term from uncomplicated pregnancies (N=63). Arteries were mounted onto a wire myograph in HCO3- -buffered physiological salt solution (PSS) at 37 degrees C (5% O2/5% CO2 bubbling) and normalised at 0.9 of L5.1 kPa. Constriction viability was assessed with 120 mmol l(-1) potassium solution (KPSS). Dose-response curves were produced with the thromboxane-mimetics U46619 and U44069 (10(-10)-2 x 10(-6)M), arginine vasopressin (10(-10)-5 x 10(-8)M) and endothelin-1 (10(-11)-3 x 10(-7)M) in the presence or absence of 50 micromol l(-1) glibenclamide. The effect of glibenclamide on arginine vasopressin- and U46619-induced constriction was also assessed in the presence of the cyclo-oxygenase inhibitor indomethacin (10 micromol l(-1)). RESULTS Pre-incubation with 50 micromol l(-1) glibenclamide significantly right-shifted dose-response curves to all vasoconstrictive agonists tested (repeated measures ANOVA). Indomethacin did not modify the inhibitory effect of glibenclamide. CONCLUSION Glibenclamide's effects on agonist-induced constrictions are unlikely to be via an inhibition of ATP-sensitive K+ channels, and with U46619- and U44069-induced constrictions, glibenclamide may be acting as a competitive antagonist of thromboxane receptors.
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Xiao D, Huang X, Longo LD, Pearce WJ, Zhang L. Regulation of baseline Ca2+ sensitivity in permeabilized uterine arteries: effect of pregnancy. Am J Physiol Heart Circ Physiol 2006; 291:H413-20. [PMID: 16501025 DOI: 10.1152/ajpheart.00103.2006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The adaptation of contractile mechanisms of the uterine artery to pregnancy is not fully understood. The present study examined the effect of pregnancy on the uterine artery baseline Ca2+ sensitivity. In beta-escin-permeabilized arterial preparations, Ca2+ -induced concentration-dependent contractions were significantly decreased in uterine arteries from pregnant animals compared with those of nonpregnant animals. Time-course studies showed that Ca2+ increased phosphorylation of 20-kDa myosin light chain (MLC20), which preceded the tension development in vessels from both pregnant and nonpregnant animals. When compared with vessels from nonpregnant animals, there was a significant increase in the protein level of MLC20 and an accordance increase in the level of Ca2+ -induced phosphorylated MLC20 (MLC20-P) in uterine arteries during pregnancy. Simultaneous measurements of MCL20-P levels and contractions stimulated with Ca2+ in the same tissues demonstrated a significant attenuation in the tension-to-MLC20-P ratio in uterine arteries during pregnancy. Activation of PKC with phorbol 12,13-dibutyrate (PDBu) potentiated Ca2+ -induced contractions in uterine arteries from nonpregnant but not pregnant animals. Accordingly, inhibition of PKC attenuated Ca2+ -induced contractions in uterine arteries from nonpregnant but not pregnant animals. PDBu produced contractions in the presence or absence of Ca2+ in the beta-escin-permeabilized arteries, which were significantly decreased in uterine arteries from pregnant compared with nonpregnant animals. The results suggest that pregnancy upregulates the thick-filament regulatory pathway by increasing MLC20 phosphorylation but downregulates the thin-filament regulatory pathway by decreasing the contractile sensitivity of MLC20-P, resulting in attenuated baseline Ca2+ sensitivity in the uterine artery. In addition, PKC plays an important role in the regulation of basal Ca2+ sensitivity, which is downregulated during pregnancy.
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Erkinaro T, Kavasmaa T, Päkkilä M, Acharya G, Mäkikallio K, Alahuhta S, Räsänen J. Ephedrine and phenylephrine for the treatment of maternal hypotension in a chronic sheep model of increased placental vascular resistance †. Br J Anaesth 2006; 96:231-7. [PMID: 16377647 DOI: 10.1093/bja/aei305] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND We hypothesized that ephedrine and phenylephrine are equal with respect to uterine and placental haemodynamics and fetal acid-base status after exposure to maternal hypoxaemia and hypotension in a chronic sheep model of increased placental vascular resistance (R(UA)). METHODS At 114-135 days gestation, chronically instrumented fetal sheep underwent placental embolization leading to increased R(UA). Twenty-four hours after embolization, the ewes were anaesthetized and randomized to receive boluses of ephedrine (n=7) or phenylephrine (n=6) for epidural-induced hypotension after maternal hypoxaemia. Uterine (Q(UtA)) and placental (Q(UA)) volume blood flows and uterine vascular resistance (R(UtA)) and R(UA) were recorded. Uterine (PI(UtA)) and umbilical artery (PI(UA)) pulsatility indices were obtained by Doppler ultrasonography. Fetal arterial blood samples were analysed for acid-base values and lactate concentrations. RESULTS During hypotension, Q(UtA), fetal pH, BE, and Po(2) decreased whereas R(UtA), PI(UtA), R(UA), and fetal lactate concentration increased. With ephedrine, Q(UtA), R(UtA), PI(UtA), R(UA), and fetal Po(2) returned to baseline. Fetal pH, BE, and lactate concentration did not change from hypotensive values. With phenylephrine, Q(UtA) remained lower (P=0.007) and R(UtA) (P=0.007), PI(UtA) (P=0.013), and R(UA) (P=0.050) higher than at baseline. Fetal Po(2) returned to baseline and fetal pH and BE did not change from hypotensive values. However, fetal lactate concentration increased further (mean difference 1.49, 95% confidence interval 0.72-2.26 mmol litre(-1); P=0.004). CONCLUSIONS In a chronic sheep model of increased placental vascular resistance, compared with ephedrine administration, phenylephrine administration was associated with impaired uterine and placental haemodynamics and increased fetal lactate concentrations.
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Sweeney M, Jones CJP, Greenwood SL, Baker PN, Taggart MJ. Ultrastructural features of smooth muscle and endothelial cells of isolated isobaric human placental and maternal arteries. Placenta 2005; 27:635-47. [PMID: 16029888 DOI: 10.1016/j.placenta.2005.05.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Revised: 05/13/2005] [Accepted: 05/14/2005] [Indexed: 11/18/2022]
Abstract
The ability of a blood vessel to develop tone is dependent upon morphological parameters of the smooth muscle cells (SMC), including density, relationship with the endothelium and subcellular distribution of myofilaments and intracellular organelles. Consequently, wall ultrastructure of isolated human placental chorionic plate arteries (n=12), fixed when pressurised to mimic their in vivo geometry, was examined qualitatively using electron microscopy, and compared with maternal arteries (omental, n=10, myometrial, n=6). Arteries from women with uncomplicated pregnancy were tested for contractile viability before fixing, with some vessels post-fixed in osmium-ferricyanide for sarcoplasmic reticulum (SR) identification. In contrast to maternal arteries, placental arteries had no internal elastic lamina but exhibited considerable extracellular matrix separating circularly orientated SMC. Human SMC contained tightly packed arrays of myofilaments running parallel to the plasma membrane, enveloping cellular organelles. Synthetic SMC, with few myofilaments and much rough SR, were observed in placental arteries only. SR in SMC from maternal arteries was located centrally, often encircling mitochondria, and also near the plasma membrane associated with caveolae. Positive SR staining was rarely observed in SMC of placental arteries. This study highlights ultrastructural differences between placental and maternal arteries that may underlie specialised mechanisms of regulating vascular tone in the placenta.
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MESH Headings
- Adult
- Chorion/blood supply
- Chorion/physiology
- Electromyography/methods
- Endothelium, Vascular/physiology
- Endothelium, Vascular/ultrastructure
- Female
- Humans
- Microscopy, Electron, Transmission
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Muscle, Smooth, Vascular/ultrastructure
- Myometrium/blood supply
- Myometrium/physiology
- Omentum/blood supply
- Omentum/physiology
- Placental Circulation/drug effects
- Placental Circulation/physiology
- Pregnancy
- Pressure
- Sarcoplasmic Reticulum/ultrastructure
- Umbilical Arteries/physiology
- Umbilical Arteries/ultrastructure
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Nakamura H, Matsuzaki I, Hatta K, Ogino K. Physiological involvement of placental endothelin-1 and prostaglandin F2alpha in uteroplacental circulatory disturbance in pregnant rats exposed to heat stress. Can J Physiol Pharmacol 2005; 82:225-30. [PMID: 15181460 DOI: 10.1139/y04-011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Several studies suggest that heat stress affects placental functions including uteroplacental circulation, subsequently leading to pregnancy failure and birth weight reduction. To clarify the involvement of endothelin and placental prostaglandin (PG) systems in the uteroplacental circulation during heat stress, we examined the effects of i.v. administration of the endothelin receptor antagonist bosentan and the cyclooxygenase inhibitor indomethacin on uteroplacental blood flow and on placental PGE2 and PGF2alpha levels and their 13,14-dyhydro-15-keto-metabolites (PGEM and PGFM, respectively) in heat-exposed or non-heat-exposed pregnant rats. The administration of bosentan or indomethacin did not change uteroplacental blood flow in non-heat-exposed pregnant rats. In contrast, heat reduced uteroplacental blood flow in pregnant rats, but the reduction was reversed by the administration of bosentan or indomethacin before heat exposure. Heat did not change placental PGE2 or PGEM levels, but in pregnant rats it increased placental PGF2alpha and PGFM levels, which were reversed by bosentan or indomethacin. Our results suggest that the activation of placental endothelin receptor and PGF2alpha systems are involved in the uteroplacental circulatory disturbances produced by heat. PGF2alpha systems activated by heat may be involved in the vasoconstricting effects of endothelin-A and -B receptors during heat exposure.
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Gogarten W, Struemper D, Gramke HF, Van Aken H, Buerkle H, Durieux M, Marcus MAE. Assessment of volume preload on uteroplacental blood flow during epidural anaesthesia for Caesarean section. Eur J Anaesthesiol 2005; 22:359-62. [PMID: 15918384 DOI: 10.1017/s026502150500061x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND OBJECTIVE Epidural and spinal anaesthesia are the preferred mode of anaesthesia for Caesarean section. Volume preloading is recommended to prevent maternal hypotension and a reduction in uteroplacental blood flow, although positive effects of volume preloading on maternal cardiac output and arterial pressure are debatable. Doppler measurements of the umbilical artery beyond deriving pulsatility indices are not routinely performed. METHODS After Institutional Review Board approval and written informed consent, 14 consecutiVe women with epidural anaesthesia for Caesarean section received either hydroxyethyl starch 500 mL or gelatine 500 mL. Haemodynamic variables monitored were maternal arterial pressure, maximal blood flow velocity and pulsatility indices of the uterine artery derived from Doppler measurements. CONCLUSIONS Maternal arterial pressure and pulsatility indices in both groups did not change from baseline after intravenous colloid infusion. However, uterine blood flow increased significantly in both groups. The effectiveness of volume preloading may therefore be better described by changes in maximum uterine blood flow velocity than by pulsatility indices or maternal arterial pressure.
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Bisseling TM, Wouterse AC, Steegers EAP, Elving L, Russel FGM, Smits P. Dysfunction of the cyclo-oxygenase pathway in the foetoplacental circulation in Type 1 diabetes mellitus. Diabet Med 2005; 22:503-6. [PMID: 15787680 DOI: 10.1111/j.1464-5491.2005.01437.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM In diabetes, perinatal morbidity is significantly increased. This may partly be related to functional changes in the foetoplacental vascular bed. In diabetes models, a defect in the cyclo-oxygenase pathway is a common observation. Therefore, we hypothesized that the human foetoplacental circulation of diabetic patients is characterized by dysfunction of the cyclo-oxygenase pathway, as well. METHODS We performed ex-vivo perfusions of isolated placental cotyledons from healthy women (n = 14) and from patients with Type 1 diabetes (n = 9). The contribution of cyclo-oxygenase products to foetoplacental vascular tone was quantified by measuring the response to the cyclo-oxygenase inhibitor indomethacin. RESULTS Baseline foetoplacental arterial pressure was comparable between controls and diabetic women (mean +/- sem, 21.7 +/- 1.2 vs. 24.4 +/- 2.0 mmHg). Maximum foetoplacental arterial pressure at highest dose of indomethacin was 32.8 +/- 3.0 mmHg in controls vs. 27.3 +/- 2.3 mmHg in diabetic women. The indomethacin-induced increase in pressure was reduced in diabetes (2.9 +/- 0.7 vs. 11.2 +/- 2.4 mmHg in controls, P = 0.01). CONCLUSIONS Under baseline conditions, the net effect of all cyclo-oxygenase products in the foetoplacental vascular bed is vasodilation. In diabetes, this vasodilator effect seems significantly impaired.
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Itakura A, Mizutani S. Involvement of placental peptidases associated with renin-angiotensin systems in preeclampsia. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2005; 1751:68-72. [PMID: 15893965 DOI: 10.1016/j.bbapap.2005.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Revised: 05/17/2004] [Accepted: 03/01/2005] [Indexed: 11/24/2022]
Abstract
Preeclampsia is characterized by pregnancy-induced hypertension accompanied with protein urea and generalized edema. Preeclampsia develops during the second half of pregnancy and resolves postpartum promptly, implicating the placenta as a primary cause in the disorder. Normal pregnancy is associated with reductions in arterial pressure and attenuated pressor response to exogenous infused angiotensin II (ANG II). In contrast, women with preeclampsia show the similar sensitivity to the pressor effect of ANG II as do non-pregnant women. To elucidate the involvement of placental peptidases associated with renin-angiotensin systems, we determined the localization of angiotensin-converting enzyme (ACE) and aminopeptidase A (AP-A), ANG II degrading enzyme, in the placenta and compared the expression of mRNA and protein in uncomplicated and preeclamptic placenta. In addition, AP-A expression in trophoblastic cells treated with ANG II and ACE expression in HUVECs under hypoxic condition were analyzed, respectively. The expression of both peptidases in the preeclamptic placenta was significantly higher than those from uncomplicated. ACE was primarily localized to venous endothelial cells of stem villous whereas AP-A expression was recognized in the trophoblast and pericytes of fetal arterioles and venules within stem villous. Hypoxia induced ACE expression in HUVECs while both hypoxia and ANG II evoked AP-A expression in trophoblast. These results suggested that hypoxic condition in preeclampsia induces ACE activation in feto-placental unit to maintain the fetal hemodynamics and placental AP-A plays a role as a component of the barrier of ANG II between mother and fetus.
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