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Abstract
Pre-eclampsia is a life-threatening disease of pregnancy unique to humans and a leading cause of maternal and neonatal morbidity and mortality. Women who survive pre-eclampsia have reduced life expectancy, with increased risks of stroke, cardiovascular disease and diabetes, while babies from a pre-eclamptic pregnancy have increased risks of preterm birth, perinatal death and neurodevelopmental disability and cardiovascular and metabolic disease later in life. Pre-eclampsia is a complex multisystem disease, diagnosed by sudden-onset hypertension (>20 weeks of gestation) and at least one other associated complication, including proteinuria, maternal organ dysfunction or uteroplacental dysfunction. Pre-eclampsia is found only when a placenta is or was recently present and is classified as preterm (delivery <37 weeks of gestation), term (delivery ≥37 weeks of gestation) and postpartum pre-eclampsia. The maternal syndrome of pre-eclampsia is driven by a dysfunctional placenta, which releases factors into maternal blood causing systemic inflammation and widespread maternal endothelial dysfunction. Available treatments target maternal hypertension and seizures, but the only 'cure' for pre-eclampsia is delivery of the dysfunctional placenta and baby, often prematurely. Despite decades of research, the aetiology of pre-eclampsia, particularly of term and postpartum pre-eclampsia, remains poorly defined. Significant advances have been made in the prediction and prevention of preterm pre-eclampsia, which is predicted in early pregnancy through combined screening and is prevented with daily low-dose aspirin, starting before 16 weeks of gestation. By contrast, the prediction of term and postpartum pre-eclampsia is limited and there are no preventive treatments. Future research must investigate the pathogenesis of pre-eclampsia, in particular of term and postpartum pre-eclampsia, and evaluate new prognostic tests and treatments in adequately powered clinical trials.
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Taylor EB, George EM. Animal Models of Preeclampsia: Mechanistic Insights and Promising Therapeutics. Endocrinology 2022; 163:6623845. [PMID: 35772781 PMCID: PMC9262036 DOI: 10.1210/endocr/bqac096] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Indexed: 11/19/2022]
Abstract
Preeclampsia (PE) is a common pregnancy-specific disorder that is a major cause of both maternal and fetal morbidity and mortality. Central to the pathogenesis of PE is the production of antiangiogenic and inflammatory factors by the hypoxic placenta, leading to the downstream manifestations of the disease, including hypertension and end-organ damage. Currently, effective treatments are limited for PE; however, the development of preclinical animal models has helped in the development and evaluation of new therapeutics. In this review, we will summarize some of the more commonly used models of PE and highlight their similarities to the human syndrome, as well as the therapeutics tested in each model.
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Affiliation(s)
- Erin B Taylor
- Correspondence: Erin B. Taylor, PhD, Department of Physiology and Biophysics, University of Mississippi Medical Center, 2500 N State St, Jackson, MS 39216-4505, USA.
| | - Eric M George
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi 39216-4505, USA
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Liu Chung Ming C, Sesperez K, Ben-Sefer E, Arpon D, McGrath K, McClements L, Gentile C. Considerations to Model Heart Disease in Women with Preeclampsia and Cardiovascular Disease. Cells 2021; 10:899. [PMID: 33919808 PMCID: PMC8070848 DOI: 10.3390/cells10040899] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/11/2021] [Accepted: 04/12/2021] [Indexed: 12/12/2022] Open
Abstract
Preeclampsia is a multifactorial cardiovascular disorder diagnosed after 20 weeks of gestation, and is the leading cause of death for both mothers and babies in pregnancy. The pathophysiology remains poorly understood due to the variability and unpredictability of disease manifestation when studied in animal models. After preeclampsia, both mothers and offspring have a higher risk of cardiovascular disease (CVD), including myocardial infarction or heart attack and heart failure (HF). Myocardial infarction is an acute myocardial damage that can be treated through reperfusion; however, this therapeutic approach leads to ischemic/reperfusion injury (IRI), often leading to HF. In this review, we compared the current in vivo, in vitro and ex vivo model systems used to study preeclampsia, IRI and HF. Future studies aiming at evaluating CVD in preeclampsia patients could benefit from novel models that better mimic the complex scenario described in this article.
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Affiliation(s)
- Clara Liu Chung Ming
- School of Biomedical Engineering/FEIT, University of Technology Sydney, Sydney, NSW 2007, Australia; (C.L.C.M.); (E.B.-S.); (D.A.)
| | - Kimberly Sesperez
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, NSW 2007, Australia; (K.S.); (K.M.); (L.M.)
| | - Eitan Ben-Sefer
- School of Biomedical Engineering/FEIT, University of Technology Sydney, Sydney, NSW 2007, Australia; (C.L.C.M.); (E.B.-S.); (D.A.)
| | - David Arpon
- School of Biomedical Engineering/FEIT, University of Technology Sydney, Sydney, NSW 2007, Australia; (C.L.C.M.); (E.B.-S.); (D.A.)
| | - Kristine McGrath
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, NSW 2007, Australia; (K.S.); (K.M.); (L.M.)
| | - Lana McClements
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Sydney, NSW 2007, Australia; (K.S.); (K.M.); (L.M.)
| | - Carmine Gentile
- School of Biomedical Engineering/FEIT, University of Technology Sydney, Sydney, NSW 2007, Australia; (C.L.C.M.); (E.B.-S.); (D.A.)
- Sydney Medical School, The University of Sydney, Sydney, NSW 2000, Australia
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
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Bakrania BA, Spradley FT, Drummond HA, LaMarca B, Ryan MJ, Granger JP. Preeclampsia: Linking Placental Ischemia with Maternal Endothelial and Vascular Dysfunction. Compr Physiol 2020; 11:1315-1349. [PMID: 33295016 PMCID: PMC7959189 DOI: 10.1002/cphy.c200008] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Preeclampsia (PE), a hypertensive disorder, occurs in 3% to 8% of pregnancies in the United States and affects over 200,000 women and newborns per year. The United States has seen a 25% increase in the incidence of PE, largely owing to increases in risk factors, including obesity and cardiovascular disease. Although the etiology of PE is not clear, it is believed that impaired spiral artery remodeling of the placenta reduces perfusion, leading to placental ischemia. Subsequently, the ischemic placenta releases antiangiogenic and pro-inflammatory factors, such as cytokines, reactive oxygen species, and the angiotensin II type 1 receptor autoantibody (AT1-AA), among others, into the maternal circulation. These factors cause widespread endothelial activation, upregulation of the endothelin system, and vasoconstriction. In turn, these changes affect the function of multiple organ systems including the kidneys, brain, liver, and heart. Despite extensive research into the pathophysiology of PE, the only treatment option remains early delivery of the baby and importantly, the placenta. While premature delivery is effective in ameliorating immediate risk to the mother, mounting evidence suggests that PE increases risk of cardiovascular disease later in life for both mother and baby. Notably, these women are at increased risk of hypertension, heart disease, and stroke, while offspring are at risk of obesity, hypertension, and neurological disease, among other complications, later in life. This article aims to discuss the current understanding of the diagnosis and pathophysiology of PE, as well as associated organ damage, maternal and fetal outcomes, and potential therapeutic avenues. © 2021 American Physiological Society. Compr Physiol 11:1315-1349, 2021.
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Affiliation(s)
- Bhavisha A. Bakrania
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Frank T. Spradley
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Surgery, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Heather A. Drummond
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Babbette LaMarca
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Michael J. Ryan
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Joey P. Granger
- Cardiovascular-Renal Research Center, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi, USA
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Saif J, Ahmad S, Rezai H, Litvinova K, Sparatore A, Alzahrani FA, Wang K, Ahmed A. Hydrogen sulfide releasing molecule MZe786 inhibits soluble Flt-1 and prevents preeclampsia in a refined RUPP mouse model. Redox Biol 2020; 38:101814. [PMID: 33321463 PMCID: PMC7744945 DOI: 10.1016/j.redox.2020.101814] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/11/2020] [Accepted: 11/25/2020] [Indexed: 12/15/2022] Open
Abstract
An imbalance in angiogenic growth factors and poor utero-placental perfusion are strongly associated with preeclampsia. The reduced utero-placental perfusion (RUPP) model that mimics insufficient placental perfusion is used to study preeclampsia. The aim of this study was to develop a refined RUPP model in C57Bl/6 J mice to test the efficacy of MZe786 as a potential inhibitor of soluble Flt-1 for preeclampsia therapy. Murine RUPP (mRUPP) was induced through bilateral ligation of the ovarian arteries at E11.5 that resulted in typical preeclampsia symptoms including increase in mean arterial pressure (MAP), kidney injury and elevated soluble Flt-1 (sFlt-1) levels in the maternal plasma and amniotic fluid. The murine RUPP kidneys showed tubular and glomerular damage along with increased oxidative stress characterised by increased nitrotyrosine staining. The mRUPP displayed abnormal placental vascular histology, reduced expression of placental cystathionine γ-lyase (CSE), the hydrogen sulfide (H2S) producing enzyme, and resulted in adverse fetal outcomes (FGR). Importantly, oral administration of hydrogen sulfide (H2S)-releasing compound MZe786 from E11.5 to E17.5 successfully prevented the development of preeclampsia. Specifically, MZe786 treatment reduced maternal MAP and kidney nitrotyrosine staining and improved fetal outcome. The circulation levels of sFlt-1 were dramatically decreased in MZe786 treated animals implying that H2S released from MZe786 offered protection by inhibiting sFlt-1 levels. MZe786 prevent preeclampsia and warrant a rapid move to randomised control clinical trial. Refined mouse reduced uterine perfusion pressure (mRUPP) model exhibits preeclampsia symptoms. Mouse RUPP induces maternal hypertension, kidney injury, elevates circulating sFlt-1 levels and promotes nitrosative stress. Mouse RUPP reduces expression of the protective enzyme, placental cystathionine γ-lyase and causes poor fetal outcome. H2S releasing aspirin, MZe786, acts as an inhibitor of sFlt-1 to successfully prevent preeclampsia and improve fetal outcome. MZe786 is a novel drug with therapeutic potential to prevent preeclampsia.
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Affiliation(s)
- Jaimy Saif
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK; Aston Medical Research Institute, Aston Medical School, Birmingham, UK
| | - Shakil Ahmad
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK; Aston Medical Research Institute, Aston Medical School, Birmingham, UK
| | - Homira Rezai
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK
| | - Karina Litvinova
- Aston Medical Research Institute, Aston Medical School, Birmingham, UK
| | - Anna Sparatore
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK; Department of Pharmaceutical Science, University of Milan, Milan, Italy
| | - Faisal A Alzahrani
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK; King Fahad Center for Medical Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Keqing Wang
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK; Aston Medical Research Institute, Aston Medical School, Birmingham, UK
| | - Asif Ahmed
- Mirzyme Therapeutics, Innovation Birmingham Campus, Faraday Wharf, Birmingham, B7 4BB, UK; King Fahad Center for Medical Research, King Abdulaziz University, Jeddah, Saudi Arabia; President's Office, University of Southampton, University Road, Southampton, UK.
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Morton JS, Levasseur J, Ganguly E, Quon A, Kirschenman R, Dyck JRB, Fraser GM, Davidge ST. Characterisation of the Selective Reduced Uteroplacental Perfusion (sRUPP) Model of Preeclampsia. Sci Rep 2019; 9:9565. [PMID: 31266978 PMCID: PMC6606748 DOI: 10.1038/s41598-019-45959-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 06/20/2019] [Indexed: 12/03/2022] Open
Abstract
Preeclampsia is a complication of pregnancy characterised by gestational hypertension, proteinuria and/or end organ disease. The reduced uteroplacental perfusion (RUPP) model, via partial occlusion of the lower abdominal aorta, mimics insufficient placental perfusion as a primary causal characteristic of preeclampsia. However, a major limitation of the RUPP model is that perfusion is reduced to the entire hindquarters of the rat resulting in hindlimb ischemia. We hypothesised that clipping the uterine and ovarian arteries in the selective (s)RUPP model would provoke signs of preeclampsia while avoiding systemic ischemia. Sham, RUPP or sRUPP procedures were performed in pregnant Sprague Dawley rats on gestational day (GD)14. On GD21 uterine blood flow was significantly reduced in both the RUPP and sRUPP models while aortic flow was reduced only in RUPP. Both models resulted in increased MAP, increased vascular oxidative stress (superoxide generation), increased pro-inflammatory (RANTES) and reduced pro-angiogenic (endoglin) mediators. Vascular compliance and constriction were unaltered in either RUPP or sRUPP groups. In summary, refinements to the RUPP model simultaneously maintain the characteristic phenotype of preeclampsia and avoid peripheral ischemia; providing a useful tool which may be used to increase our knowledge and bring us closer to a solution for women affected by preeclampsia.
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Affiliation(s)
- J S Morton
- Faculty of Medicine and Dentistry, Dept. of Ob/Gyn, University of Alberta, Edmonton, AB, T6G 2S2, Canada.,Women and Children's Health Research Institute, Edmonton, AB, T6G 2R3, Canada
| | - J Levasseur
- Faculty of Medicine and Dentistry, Dept. of Pediatrics, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - E Ganguly
- Faculty of Medicine and Dentistry, Dept. of Ob/Gyn, University of Alberta, Edmonton, AB, T6G 2S2, Canada.,Faculty of Medicine and Dentistry, Dept. of Physiology, University of Alberta, Edmonton, AB, T6G 2H7, Canada.,Women and Children's Health Research Institute, Edmonton, AB, T6G 2R3, Canada
| | - A Quon
- Faculty of Medicine and Dentistry, Dept. of Ob/Gyn, University of Alberta, Edmonton, AB, T6G 2S2, Canada.,Women and Children's Health Research Institute, Edmonton, AB, T6G 2R3, Canada
| | - R Kirschenman
- Faculty of Medicine and Dentistry, Dept. of Ob/Gyn, University of Alberta, Edmonton, AB, T6G 2S2, Canada.,Women and Children's Health Research Institute, Edmonton, AB, T6G 2R3, Canada
| | - J R B Dyck
- Faculty of Medicine and Dentistry, Dept. of Pediatrics, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - G M Fraser
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, A1B 3V6, Canada
| | - S T Davidge
- Faculty of Medicine and Dentistry, Dept. of Ob/Gyn, University of Alberta, Edmonton, AB, T6G 2S2, Canada. .,Faculty of Medicine and Dentistry, Dept. of Physiology, University of Alberta, Edmonton, AB, T6G 2H7, Canada. .,Women and Children's Health Research Institute, Edmonton, AB, T6G 2R3, Canada.
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7
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Martinez-Fierro ML, Hernández-Delgadillo GP, Flores-Morales V, Cardenas-Vargas E, Mercado-Reyes M, Rodriguez-Sanchez IP, Delgado-Enciso I, Galván-Tejada CE, Galván-Tejada JI, Celaya-Padilla JM, Garza-Veloz I. Current model systems for the study of preeclampsia. Exp Biol Med (Maywood) 2018; 243:576-585. [PMID: 29415560 DOI: 10.1177/1535370218755690] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Preeclampsia (PE) is a pregnancy complex disease, distinguished by high blood pressure and proteinuria, diagnosed after the 20th gestation week. Depending on the values of blood pressure, urine protein concentrations, symptomatology, and onset of disease there is a wide range of phenotypes, from mild forms developing predominantly at the end of pregnancy to severe forms developing in the early stage of pregnancy. In the worst cases severe forms of PE could lead to systemic endothelial dysfunction, eclampsia, and maternal and/or fetal death. Worldwide the fetal morbidity and mortality related to PE is calculated to be around 8% of the total pregnancies. PE still being an enigma regarding its etiology and pathophysiology, in general a deficient trophoblast invasion during placentation at first stage of pregnancy, in combination with maternal conditions are accepted as a cause of endothelial dysfunction, inflammatory alterations and appearance of symptoms. Depending on the PE multifactorial origin, several in vitro, in vivo, and in silico models have been used to evaluate the PE pathophysiology as well as to identify or test biomarkers predicting, diagnosing or prognosing the syndrome. This review focuses on the most common models used for the study of PE, including those related to placental development, abnormal trophoblast invasion, uteroplacental ischemia, angiogenesis, oxygen deregulation, and immune response to maternal-fetal interactions. The advances in mathematical and computational modeling of metabolic network behavior, gene prioritization, the protein-protein interaction network, the genetics of PE, and the PE prediction/classification are discussed. Finally, the potential of these models to enable understanding of PE pathogenesis and to evaluate new preventative and therapeutic approaches in the management of PE are also highlighted. Impact statement This review is important to the field of preeclampsia (PE), because it provides a description of the principal in vitro, in vivo, and in silico models developed for the study of its principal aspects, and to test emerging therapies or biomarkers predicting the syndrome before their evaluation in clinical trials. Despite the current advance, the field still lacking of new methods and original modeling approaches that leads to new knowledge about pathophysiology. The part of in silico models described in this review has not been considered in the previous reports.
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Affiliation(s)
- M L Martinez-Fierro
- 1 Molecular Medicine Laboratory, Unidad Académica de Medicina Humana y Ciencias de la Salud, Universidad Autónoma de Zacatecas, 98160 Zacatecas, México.,2 Posgrado en Ingeniería y Tecnología Aplicada, Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, 98000 Zacatecas, México
| | - G P Hernández-Delgadillo
- 3 Laboratorio de Investigación en Farmacología, 27779 Universidad Autónoma de Zacatecas , 98160 Zacatecas, México
| | - V Flores-Morales
- 4 Laboratorio de Síntesis Asimétrica y Bioenergética (LSAyB), 27779 Universidad Autónoma de Zacatecas , 98160 Zacatecas, México
| | - E Cardenas-Vargas
- 1 Molecular Medicine Laboratory, Unidad Académica de Medicina Humana y Ciencias de la Salud, Universidad Autónoma de Zacatecas, 98160 Zacatecas, México.,5 Hospital General Zacatecas "Luz Gonzalez Cosio", Secretaria de Salud de Zacatecas, 98160 Zacatecas, México
| | - M Mercado-Reyes
- 6 Laboratorio de Biología de la Conservación, Unidad Académica de Ciencias Biológicas, 27779 Universidad Autónoma de Zacatecas , 98060 Zacatecas, México
| | - I P Rodriguez-Sanchez
- 7 Departamento de Génetica, Facultad de Medicina, Universidad Autonoma de Nuevo Leon, 64460 Monterrey, México
| | - I Delgado-Enciso
- 8 Faculty of Medicine, Universidad de Colima, 28040 Colima, Mexico.,9 State Cancer Institute, Health Secretary of Colima, 28060 Colima, Mexico
| | - C E Galván-Tejada
- 10 Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, 98000 Zacatecas, México
| | - J I Galván-Tejada
- 10 Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, 98000 Zacatecas, México
| | - J M Celaya-Padilla
- 10 Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, 98000 Zacatecas, México.,11 CONACYT - Universidad Autónoma de Zacatecas, 98000 Zacatecas, México
| | - I Garza-Veloz
- 1 Molecular Medicine Laboratory, Unidad Académica de Medicina Humana y Ciencias de la Salud, Universidad Autónoma de Zacatecas, 98160 Zacatecas, México.,2 Posgrado en Ingeniería y Tecnología Aplicada, Unidad Académica de Ingeniería Eléctrica, Universidad Autónoma de Zacatecas, 98000 Zacatecas, México
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George EM, Granger JP. Recent insights into the pathophysiology of preeclampsia. ACTA ACUST UNITED AC 2014; 5:557-566. [PMID: 21170149 DOI: 10.1586/eog.10.45] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Preeclampsia, characterized by new-onset gestational hypertension and proteinuria, is a common and serious complication of pregnancy. Evidence from both animal and human studies has implicated placental ischemia and hypoxia as a central causative factor in the etiology of the disorder. The ischemic placenta in turn initiates a cascade of secondary effector mechanisms, including altered proangiogenic and antiangiogenic factor balance, increase in maternal oxidative stress and endothelial and immunological dysfunction. The full elucidation of these mechanisms will hopefully lead to a more complete understanding of the etiology of preeclampsia and lead to successful therapeutic intervention through the targeted disruption of new and novel pathways.
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Affiliation(s)
- Eric M George
- Department of Physiology and Biophysics and the Center for Excellence in Cardiovascular-Renal Research, University of Mississippi Medical Center, 2500 N. State Street, Jackson, MS 39216, USA
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Schenone MH, Schlabritz-Loutsevitch N, Zhang J, Samson JE, Mari G, Ferry RJ, Hubbard GB, Dick EJ. Abruptio placentae in the baboon (Papio spp.). Placenta 2012; 33:278-84. [PMID: 22265925 DOI: 10.1016/j.placenta.2011.12.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 12/22/2011] [Accepted: 12/27/2011] [Indexed: 10/14/2022]
Abstract
INTRODUCTION Placental abruption is a serious condition that increases perinatal morbidity and mortality. Clinical prevention and treatment options are limited, especially in human preterm deliveries. Knowledge of the mechanisms that keep the placenta in place during pregnancy is critical for developing strategies for the prevention of abruption. Failure of physiological transformation of spiral arteries has been described as a major contributing factor of the placental abruption development. Baboons (Papio spp.) share striking similarities with humans in regard to placental structure, utero-placental blood flow, and fetal development; however, the mode of trophoblast invasion is shallow in baboons. This fact prompted the hypothesis that the incidence of placental abruption will be increased in baboons compared to humans. MATERIAL AND METHODS Baboon placentas were collected between 2002 and 2008. Two independent veterinary pathologists evaluated the slides. A certified physician pathologist performed additional histology. RESULTS Placental abruption was diagnosed in 22 baboons among 2423 live births during the study period (0.9% prevalence). The most common clinical presentations were fetal demise and vaginal bleeding. The most common pathological findings were intraplacental hemorrhages with or without hematoma formation (86.4%). Other findings consisted of neutrophil infiltration (50%), decidual necrosis (22.7%), decidual vascular congestion and inflammation, villous congestion and retroplacental hemorrhage/hematoma (each 18.2%). These pathologic findings were the same for term and preterm deliveries. CONCLUSION This is the first systematic study of placental abruption in non-human primates, analyzing a large colony of baboons. Despite differences in trophoblast invasion, the clinical features observed in placental abruption affecting baboons resembled those reported in humans. The cluster of placental pathological findings in baboons also agreed with clinical reports, but the prevalence of these findings differed between baboons and humans. We discuss a mechanism of anti-abruption forces that offset shallow trophoblast invasion observed in baboons.
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Affiliation(s)
- M H Schenone
- Department of Obstetrics and Gynecology, University of Tennessee Health Science Center, Memphis, TN 38103-2896, USA
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Ryan MJ, Gilbert EL, Glover PH, George EM, Masterson CW, McLemore GR, LaMarca B, Granger JP, Drummond HA. Placental ischemia impairs middle cerebral artery myogenic responses in the pregnant rat. Hypertension 2011; 58:1126-31. [PMID: 22068864 DOI: 10.1161/hypertensionaha.111.181453] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
One potential mechanism contributing to the increased risk for encephalopathies in women with preeclampsia is altered cerebral vascular autoregulation resulting from impaired myogenic tone. Whether placental ischemia, a commonly proposed initiator of preeclampsia, alters cerebral vascular function is unknown. This study tested the hypothesis that placental ischemia in pregnant rats (caused by reduced uterine perfusion pressure [RUPP]) leads to impaired myogenic responses in middle cerebral arteries. Mean arterial pressure was increased by RUPP (135±3 mm Hg) compared with normal pregnant rats (103±2 mm Hg) and nonpregnant controls (116±1 mm Hg). Middle cerebral arteries from rats euthanized on gestation day 19 were assessed in a pressure arteriograph under active (+Ca(2+)) and passive (0 Ca(2+)) conditions, whereas luminal pressure was varied between 25 and 150 mm Hg. The slope of the relationship between tone and pressure in the middle cerebral artery was 0.08±0.01 in control rats and was similar in normal pregnant rats (0.05±0.01). In the RUPP model of placental ischemia, this relationship was markedly reduced (slope=0.01±0.00; P<0.05). Endothelial dependent and independent dilation was not different between groups, nor was there evidence of vascular remodeling assessed by the wall:lumen ratio and calculated wall stress. The impaired myogenic response was associated with brain edema measured by percentage of water content (RUPP P<0.05 versus control and normal pregnant rats). This study demonstrates that placental ischemia in pregnant rats leads to impaired myogenic tone in the middle cerebral arteries and that the RUPP model is a potentially important tool to examine mechanisms leading to encephalopathy during preeclamptic pregnancies.
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Affiliation(s)
- Michael J Ryan
- Department of Physiology and Biophysics, University of Mississippi Medical Center, 2500 North State St, Jackson, MS 39047, USA.
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11
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Hutten JWM, Kuijpers JC, Velzen DV, Wallenburg HCS. Pathogenesis of Pregnancy-Induced Hypertensive Disorders A Review of Experimental Animal Models. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10641959109012916] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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12
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Eder DJ, McDonald MT. A Role for Brain Angiotensin II in Experimental Pregnancy-Induced Hypertension in Laboratory Rats. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10641958709023492] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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14
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Gilbert JS, Ryan MJ, LaMarca BB, Sedeek M, Murphy SR, Granger JP. Pathophysiology of hypertension during preeclampsia: linking placental ischemia with endothelial dysfunction. Am J Physiol Heart Circ Physiol 2007; 294:H541-50. [PMID: 18055511 DOI: 10.1152/ajpheart.01113.2007] [Citation(s) in RCA: 347] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Studies over the last decade have provided exciting new insights into potential mechanisms underlying the pathogenesis of preeclampsia. The initiating event in preeclampsia is generally regarded to be placental ischemia/hypoxia, which in turn results in the elaboration of a variety of factors from the placenta that generates profound effects on the cardiovascular system. This host of molecules includes factors such as soluble fms-like tyrosine kinase-1, the angiotensin II type 1 receptor autoantibody, and cytokines such as tumor necrosis factor-alpha, which generate widespread dysfunction of the maternal vascular endothelium. This dysfunction manifests as enhanced formation of factors such as endothelin, reactive oxygen species, and augmented vascular sensitivity to angiotensin II. Alternatively, the preeclampsia syndrome may also be evidenced as decreased formation of vasodilators such as nitric oxide and prostacyclin. Taken together, these alterations cause hypertension by impairing renal pressure natriuresis and increasing total peripheral resistance. Moreover, the quantitative importance of the various endothelial and humoral factors that mediate vasoconstriction and elevation of arterial pressure during preeclampsia remains to be elucidated. Thus identifying the connection between placental ischemia/hypoxia and maternal cardiovascular abnormalities in hopes of revealing potential therapeutic regimens remains an important area of investigation and will be the focus of this review.
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Affiliation(s)
- Jeffrey S Gilbert
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216-4505, USA
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Abstract
There have been many attempts to produce animal models that mimic the hypertensive disorders of pregnancy, especially preeclampsia, but most are incomplete when compared to the full spectrum of the human disease. This review assesses a number of these models, organized according to the investigators attempt to focus on a specific pathogenic mechanism believed to play a role in the human disease. These mechanisms include uterine ischemia, impairments in the nitric oxide system, insulin resistance, overactivity of the autonomic nervous and/or renin-angiotensin systems, activation of a systemic inflammatory response, and most recently, activation of circulating proteins that interfere with angiogenesis. In addition a model of renal disease that mimics superimposed preeclampsia is discussed. Defining these animal models should help in our quest to understand the cause, as well as to test preventative and therapeutic strategies in the management of these hypertensive disorders of pregnancy.
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Affiliation(s)
- Eduardo Podjarny
- Department of Nephrology and Hypertension, Meir Hospital, Sackler Faculty of Medicine, Tel-Aviv University, Israel
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Henzel MK, Alsip NL. Systemic vascular reactivity in an aortic coarctation model of preeclampsia in the rat. PATHOPHYSIOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR PATHOPHYSIOLOGY 2001; 8:133-140. [PMID: 11720810 DOI: 10.1016/s0928-4680(01)00075-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Preeclampsia (preECL), a hypertensive disorder of pregnancy, which occurs only in humans, is dangerous for mother and fetus. It may be caused by placental hypoxia triggering the release of a circulating factor that damages the maternal endothelium leading to vasoconstriction and hypertension. Our primary objective was to determine if systemic vascular reactivity is altered in a rat aortic coarctation (ACOR) model of preECL. We hypothesized that reduced blood flow to the rat utero-placental unit would lead to increased responsiveness to vasoconstrictors. On day 8 of pregnancy, rats were anesthetized and subjected to sham (SHAM) or aortic coarctation (ACOR) surgery by placing a 0.4 mm diameter silver clip distal to the renal arteries. Systemic pressor responses to bolus doses of phenylephrine (PE), angiotensin II (AII), and 5-hydroxytryptamine (5-HT) were determined in these animals on gestation days 14-15 (mid-pregnancy) or 19-20 (late pregnancy). Virgin rats were subjected to sham or ACOR surgery and arterial pressure measured 10-11 days after surgery. Arterial pressure was elevated in late pregnant ACOR animals (mean of 120+/-4 mmHg) compared with SHAM (mean of 101+/-6), but mid-pregnant and virgin groups were not different. Proteinuria was present more frequently in late pregnant ACOR animals (86%) than in SHAM (41%), but there were no differences in average fetal weight, fetal number, or number of reabsorbed fetuses. Pressor responses were not different in ACOR and SHAM groups in mid- or late pregnancy. These data indicate that the aortic coarctation to 0.4 mm in the rat mimics the clinical presentation of mild preECL in humans.
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Affiliation(s)
- M Kristina Henzel
- Department of Physiology and Biophysics, Health Sciences Center, University of Louisville, 40292, Louisville, KY, USA
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Abstract
Some of the maternal symptoms of preeclampsia can be produced by uterine ischemia, although no quadriped spontaneously exhibits this disease. It may be that the combination of upright posture and uteroplacental ischemia are necessary for manifestation of the full syndrome. Chronic nitric oxide synthase inhibition in rats produces a pattern of change that resembles the symptoms of preeclampsia, and the preeclamptic-like response of rats with adriamycin nephropathy and hyperinsulinemia is associated with endothelial dysfunction. These models are definitely of use in preeclampsia research, but because this disease only occurs spontaneously in primates, the definitive studies on preeclampsia will, of necessity, be clinical.
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Affiliation(s)
- E Podjarny
- Department of Nephrology and Hypertension, Meir Hospital, Sackler Faculty of Medicine, Tel-Aviv University, Israel
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Ramsay MM, Tame JD, Winter JA, Carbone LG, Schlafer DH, Nathanielsz PW. Proteinuric hypertension in a pregnant baboon: was this pre-eclampsia? J Med Primatol 1997; 26:207-12. [PMID: 9416572 DOI: 10.1111/j.1600-0684.1997.tb00054.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We report the results of investigating a pregnant baboon that developed hypertension, proteinuria, and oedema in late gestation. Although the clinical presentation suggested a diagnosis of pre-eclampsia, the evolution of her clinical signs and results of a renal biopsy performed 3 weeks after delivery suggested that glomerulonephritis was the underlying disease.
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Affiliation(s)
- M M Ramsay
- Laboratory for Pregnancy and Newborn Research, School of Veterinary Medicine, Cornell University, Ithaca, NY 14853-6401, USA
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Schafer W, Tielsch J, Casper FW, Seufert RJ, Zahradnik HP. Urinary excretion of 6-keto-PGF1 alpha TxB2 and PGE2 in a rat animal model for preeclampsia-like syndrome. PROSTAGLANDINS 1993; 46:167-75. [PMID: 8210446 DOI: 10.1016/0090-6980(93)90042-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The etiology of pregnancy induced hypertension (PIH) is still unknown. The pathophysiology must be clarified. In this paper we present an animal model where hypertension in pregnant and non-pregnant rats was induced by an experimental reduction of uteroplacental blood flow. Thus, a preeclampsia-like syndrome could be studied under defined conditions. The eicosanoid system was investigated for pathophysiological alterations of the kidney by measuring urinary excretion of 6-keto-PGF1 alpha, TxB2 and PGE2 with radioimmunoassay at day 18 of pregnancy. First, in gravid control animals concentrations of all three prostaglandins were significantly elevated compared to non-gravid controls. However, in hypertensive gravid rats urinary concentrations of these prostaglandins fell even below the levels of non-gravid controls. The observed decrease was more pronounced for the vasodilatory 6-keto-PGF1 alpha and PGE2 than for the vasoconstrictive TxB2. Our results demonstrate that an experimental reduction of uteroplacental blood flow in the rat culminates in symptoms which clinically (hypertension, proteinuria) and pathophysiologically (eicosanoid system) resemble to preeclampsia.
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Combs CA, Katz MA, Kitzmiller JL, Brescia RJ. Experimental preeclampsia produced by chronic constriction of the lower aorta: validation with longitudinal blood pressure measurements in conscious rhesus monkeys. Am J Obstet Gynecol 1993; 169:215-23. [PMID: 8333460 DOI: 10.1016/0002-9378(93)90171-e] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVES Our goals were (1) to determine whether hypertension, proteinuria, and glomerular endotheliosis can be produced by chronic reduction of lower aortic pressure in pregnant rhesus monkeys and (2) to study the time course of the development of hypertension by means of longitudinal arterial blood pressure measurements in conscious, unrestrained pregnant rhesus monkeys. STUDY DESIGN Indwelling arterial catheters were placed at 103 +/- 4 days of gestation (term 160 days) for measurement of arterial pressure before and after reduction of lower aortic pressure. At 116 +/- 7 days lower aortic pressure was reduced by 24 +/- 11 mm Hg in 11 monkeys (experimental group) by a stricture on the aorta just below the renal arteries; six monkeys (controls) underwent a sham operation. Resting on the aorta just below the renal arteries; six monkeys (controls) underwent a sham operation. Resting pressures were measured three to five times per week by a tether-and-swivel system. RESULTS Baseline arterial pressure averaged 81 +/- 6 mm Hg. In the experimental group four monkeys had adverse outcomes (one maternal death with severe hypertension, one abruptio placentae with stillbirth, and two spontaneous preterm deliveries with hypertension). There was one preterm delivery in the control group. Of the seven monkeys with aortic stricture who continued to term, four developed sustained hypertension (mean pressure 18 +/- 6 mm Hg above baseline), proteinuria, and moderate-to-severe glomerular endotheliosis. None of the controls had hypertension or proteinuria, but two had endotheliosis. CONCLUSION These observations confirm that a syndrome resembling preeclampsia can be produced by a reduction of lower aortic pressure, and they demonstrate that the associated hypertension is not an artifact of anesthesia. This model may prove useful in studying the pathophysiologic mechanisms of preeclampsia.
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Affiliation(s)
- C A Combs
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco
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Clark DA. On preeclampsia and leukocytes in human decidua. AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY AND MICROBIOLOGY : AJRIM 1987; 15:9-11. [PMID: 3322069 DOI: 10.1111/j.1600-0897.1987.tb00142.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- D A Clark
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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Tulenko T, Schneider J, Floro C, Sicilla M. The in vitro effect on arterial wall function of serum from patients with pregnancy-induced hypertension. Am J Obstet Gynecol 1987; 156:817-23. [PMID: 3578395 DOI: 10.1016/0002-9378(87)90337-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The object of this study was to develop an in vitro model to identify the serum factor(s) responsible for the vascular changes that occur in pregnancy-induced hypertension (preeclampsia). Segments of rabbit carotid artery were perfused for 3 hours with nutrient medium to which serum from normal pregnant women or patients with preeclampsia was added. After perfusion, ring segments of the vessels were cut and mounted in muscle chambers for force measurement. Sensitivity of the vessels to constrictor agents and endothelium-mediated relaxation was studied. The results indicate that arteries exposed to serum from preeclamptic patients developed a 2.9-fold increase in sensitivity to angiotensin II, 1.6-fold increased sensitivity to norepinephrine, and no change of sensitivity to serotonin. These effects were not accompanied by changes in isometric force. Endothelium-mediated relaxation was not affected by serum from preeclamptic patients. These findings confirm clinical observations of increased angiotensin II sensitivity in preeclampsia. The system used may facilitate identification of factors that cause the difference between the sera of normal pregnant women and those with preeclampsia.
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Rao PS, Cavanagh D, Gaston LW. Endotoxic shock in the primate: effects of aspirin and dipyridamole administration. Am J Obstet Gynecol 1981; 140:914-22. [PMID: 7270604 DOI: 10.1016/0002-9378(81)90085-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A primate model was utilized to study the cardiovascular and coagulation effects of endotoxic shock. The therapeutic effectiveness of drugs such as aspirin and dipyridamole, which diminish platelet aggregation and adherence, were evaluated. From the data, it appears that the kidney is a target organ in endotoxic shock, at least when a bolus injection of endotoxin is administered. The precipitate falls in the renal artery flow (p less than 0.01) and platelet count (p less than 0.01), which occur 3 minutes after the intravenous injection of endotoxin, can be prevented in part by pretreatment with aspirin (40 mg/kg of body weight). The changes in the coagulation profile were of less magnitude, and the fibrin degradation products appeared late in the group pretreated with aspirin as compared to the other groups. The combination of dipyridamole and aspirin was not as effective as aspirin alone in achieving the apparently protective effect. The study suggests that the administration of aspirin to patients with gram-negative infections may be beneficial.
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Abstract
In 39 pregnant and six nonpregnant dogs the abdominal aorta was exposed extraperitoneally through a left paralumbar incision, and a vascular occluder and a flow transducer were placed around it. The tubing of the occluder and the wiring of the flow transducer were slipped under the skin and advanced to the back of the neck of the animal. Thus, the aortic blood flow could be progressively reduced and continuously monitored. After 4 to 20 days of blood flow reduction of 35% to 75%, the picture of a moderately severe toxemia appeared in 10 dogs and that of a mild toxemia was seen in the 11 others. Nine animals were eliminated because of premature labor and three were eliminated for surgical complications. The control group (six pregnant animals with a sham operation and six nonpregnant animals with a severe aortic constriction) presented no abnormalities.
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Lynch A, Mychalkiw W. Prenatal progesterone II. Its role in the treatment of pre-eclamptic toxaemia and its effect on the off-spring's intelligence: a reappraisal. Early Hum Dev 1978; 2:323-39. [PMID: 750192 DOI: 10.1016/0378-3782(78)90060-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Dalton's results concerning the beneficial effect of progesterone supplementation in preventing pre-eclamptic toxaemia [16] and in enhancing intellectual potential [17,18] were reappraised. We could find no evidence in the data that progesterone supplementation was any better at preventing pre-eclamptic toxaemia than treating the disorder symptomatically. Nor could we find any convincing evidence that excess progesterone enhances development at 1 yr of age, academic attainment at 9--10 yr of age, or success in school leaving examinations and improves the chances of continuing further full-time education after leaving school.
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Mitchell GG, Mellor S, Burslem RW. Pregnancy following bilateral uterine artery ligation. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1977; 84:551-4. [PMID: 911714 DOI: 10.1111/j.1471-0528.1977.tb12645.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A successful pregnancy following bilateral uterine artery ligation performed in an attempt to relieve dysfunctional menorrhagia is reported. Serial biparietal diameters showed a normal growth curve and the newborn infant weighed 2640 g. The patient was normotensive throughtout the pregnancy. Prior to uterine artery ligation, she had had four pregnancies but there were no surviving children. It is suggested that uterine artery ligation may have a limited place in the management of patients with dysfunctional menorrhagia.
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Abstract
Pre-eclamptic toxaemia is a common complication of late pregnancy. However, the occurrence of clinically unsuspected laryngeal oedema has not, to the authors' knowledge, been described previously. Experience of such a case leads them to recommend that a selection of tracheal tubes ranging from 8 to 4-5 mm, be available when anaesthesia is undertaken in patients who have oedema associated with pre-eclamptic toxaemia.
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Abstract
In order to develop a model for the study of eclamptogenic toxemia, a series of experiments were carried out on 31 female baboons. In Group 1, consisting of 10 animals, metal clips were placed around the uterine arteries in order to partially occlude them, and the ovarian vessels were transected. The animals were subsequently mated. Nine developed hypertension and proteinuria, and one aborted. The renal lesions in these animals were indistinguishable from those described in human toxemia. Group 2 consisted of three of the 10 baboons from Group 1, which became pregnant a second time. They again developed hypertension and proteinuria. In Group 3, three baboons at 100 days of gestation were treated as in Group 1 with similar results. Groups 4 and 5 served as pregnant (3) and nonpregnant (15) controls. It is concluded that a toxemia model has been developed in a subhuman primate. This model will prove useful in the further study of eclamptogenic toxemia.
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Pritchard JA, Cunningham FG, Mason RA. Coagulation changes in eclampsia: their frequency and pathogenesis. Am J Obstet Gynecol 1976; 124:855-64. [PMID: 1258945 DOI: 10.1016/s0002-9378(16)33390-7] [Citation(s) in RCA: 144] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The maternal coagulation mechanism has been investigated in an effort to identify its role, if any, in the pathogenesis of eclampsia. Thrombocytopenia was identified in 28 of 95 cases (29 per cent), a prolonged thrombin time in 19 of 38 (50 per cent), abnormally elevated serum fibrinogen-fibrin degradation products in two of 65 (3 per cent), and circulating fibrin monomer in one out of 20 (5 per cent). Overt hemolysis was rare (2 per cent). Thus the pattern as well as the degree of change in the maternal coagulation mechanism differed remarkably from that typical of severe abruptio placentae and of prolonged retention of a dead fetus, the classic obstetric models of fast and slow disseminated intravascular coagulation. It is concluded that the coagulation changes when present in eclampsia are effect rather than cause. Moreover, the changes may evolve primarily from platelet adherence at sites of vascular endothelial damage as the consequence of segmental vasospasm and vasodilatation rather than be triggered by the escape of thromboplastin from the placenta into the maternal circulation.
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