Mechanisms of Pregnancy Vascular Adaptations

NCT03806283 | Recruiting

• 6 other identifiers: 2025-13525R01HL134779-02A532860SMPH/OBSTET & GYNECOL/OBSTETProtocol Version 12/23/20252018-1368
• Study Type: observational
• Target: 166
• Locations: 1 country
• Sites: 1

Brief Summary

The investigators will collect omental tissue (research surgical excision) and placental tissue (standard of care clinical delivery) from both preeclamptic and non-preeclamptic women during their c-section and use these samples to study the blood vessels, specifically the expression/activation of the AT2R.

Conditions

Pre-Eclampsia; Vascular Diseases

Outcome Measures

Primary Outcomes (3)

• Quantify the vascular AT2R expression and vascular function in placental and omental vascular arteries in both preeclamptic and controlled pregnancies.

  The researchers will measure the amount and distribution of vascular angiotensin II type 1 receptor (AT1R) and AT2R during normal human pregnancy and in preeclampsia. The researchers will assess if AT2R expression varies with severity of preeclampsia. Based on pilot data, the researchers expect decreased AT2R and increased AT1R protein levels in preeclamptic vs normotensive vessels.

  1 year

• To test if ex-vivo treatment of AT2R agonists reverses the endothelial dysfunction and improves vasoconstriction in the preeclamptic vessels.

  The researchers will quantify vascular AT2R expression and vascular function in placental and omental arteries of preeclamptic vs normal pregnant women. Vascular function studies will also test if ex vivo treatment with AT2R agonist reverses endothelial dysfunction and vasoconstriction in preeclamptic vessels.

  1 year

• To test AT2R mediated mechanisms on endothelial derived hyperpolarizing factor, nitric oxide and prostacyclin pathway of vascular relaxation to examine AT2's role in vaso-relaxation and AT2R mediated vasoconstrictor pathway will be defined.

  To test the AT2R-mediated mechanisms, endothelium-derived hyperpolarizing factor (EDHF), nitric oxide, and prostacyclin (PGI2) pathways of vascular relaxation and AT1R-mediated vasoconstrictor pathways will be determined. Also, the expression of endothelial nitric oxide synthase, its activity state, and signaling components of EDHF and PGI2 pathways, as well as nitrate/nitrite and PGI2 production and changes in membrane potential, will be measured

  1 year

Study Arms (2)

Cohort 1 no Preeclampsia

Cohort 1: mothers with no diagnosis of preeclampsia during pregnancy Omental Biopsy and placental collection will be performed

Procedure: Omental Biopsy

Cohort 2 mild or severe Preeclampsia

Cohort 2: mothers with diagnosis of mild or severe preeclampsia during pregnancy Omental Biopsy and placental collection will be performed

Procedure: Omental Biopsy

Interventions

Omental Biopsy PROCEDURE

The surgeon and clinical care team will conduct the c-section to deliver the baby and the placenta as clinically indicated. After delivery, during the closing procedures, the surgeon will indicate a time for a participating Ob/Gyn physician on the study team to collect the omental bio-specimen. Omentum is frequently excised or removed for clinical reasons during surgical procedures. Omentum has small blood vessels within it that have been used for evaluation of vascular functional changes in research. The investigators wish to isolate one to three vessels of 5 to 7 cm length. The surgeon will then close and the clinical care team will resume their standard of care activities.

Cohort 1 no Preeclampsia; Cohort 2 mild or severe Preeclampsia

Eligibility Criteria

• Age: 18 Years - 40 Years
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Pregnant women with or without Preeclampsia who will be undergoing a C-section

You may qualify if:

• Female
• Ages 18 to 40 years old
• Singleton gestation between 28 weeks, 0 days and 41 weeks, 0 days gestational age at the time of consent
• Undergoing caesarean section, either planned or otherwise with or without trial of labor

You may not qualify if:

• Treatment of severe hypertension by antihypertensive or use of magnesium sulfate after the patient is hospitalized for the diagnosis of preeclampsia.
• Any major fetal structural anomalies or aneuploidies
• Undergoing cesarean section for placental abruption or bleeding complications.
• Singleton gestation not within 36 weeks, 0 days and 41 weeks, 0 days gestational age at the time of enrollment (delivery)

Sponsors & Collaborators

• University of Wisconsin, Madison: lead
• National Heart, Lung, and Blood Institute (NHLBI): collaborator

Study Sites (1)

UnityPoint Health-Meriter Hospital

Madison, Wisconsin, 53715, United States

RECRUITING

Biospecimen

Retention: SAMPLES WITHOUT DNA

omental tissue (research surgical excision) placental tissue (standard of care clinical delivery)

MeSH Terms

Conditions

Pre-Eclampsia; Vascular Diseases

Condition Hierarchy (Ancestors)

Hypertension, Pregnancy-Induced; Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Cardiovascular Diseases

Study Officials

• Sathish Kumar, PhD

  University of Wisconsin, Madison

  PRINCIPAL INVESTIGATOR

Central Study Contacts

UW Ob/Gyn Human Subjects Core

CONTACT

608-890-3345; research.crc_obgyn@wisc.edu

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 14, 2019
• First Posted: January 16, 2019
• Study Start: November 20, 2018
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): April 1, 2027
• Last Updated: January 20, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)