Forebrain Electroneutral Transporters in Salt-sensitive Hypertension: an MRI Study

March 20, 2026 updated by: University of Delaware
The overall objective of this project is to identify the key salt-sensing regions of the brain and determine the underlying mechanism of sodium sensing. The investigators will assess how the brain responds to an acute increase of salt in the blood using MRI. This will be done during a 30-minute infusion of a saline solution containing 3% salt. One trial will be conducted with a salt sensing channel blocker and one trial without the salt sensing channel blocker. This will help to assess the role of a specific salt sensing channel in the brain. Salt sensitivity of BP will be assessed using 7-day dietary feeding where participants will be given food to consume for 7-days. Comparisons will be made between salt resistant (no change in blood pressure going from low to high salt diets) and salt sensitive adults (a change in blood pressure going from low to high salt diets). The investigators think the changes in MRI will be greater in salt sensitive compared to salt resistant subjects.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The ability of the brain to sense changing sodium levels in the blood is critical in mediating the neurohumoral responses to hypernatremia, however, the mechanisms underlying sodium sensing in humans is poorly understood. The purpose of this study is to identify key sodium-sensing regions of the human brain in middle-aged men and women with high blood pressure and determine if the Na-K-2Cl co-transporter (NKCC2) mediates the neurohumoral response to acute hypernatremia. The investigators plan on comparing these central sodium responses to acute hypernatremia between salt-sensitive and salt-resistant adults. In this randomized double-blinded crossover study subjects will have a 3% NaCl (hypertonic saline) infusion with or without NKCC2 antagonism (furosemide). Completion of this project will increase the understanding of blood pressure regulation, which has major public health implications.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
120

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Age: > 40 years or < 60 years
  • Blood pressure: > 100/60 mmHg or < 140/90 mmHg
  • BMI: > 18.5 kg/m2 or < 35 kg/m2
  • Serum potassium: > 3.5 mmol/L or < 5.5 mmol/L
  • No history of cardiovascular, renal, metabolic, or neurological disease

Exclusion Criteria:

  • Age: < 40 years or > 60 years
  • Blood pressure: < 100/60 mmHg or > 140/90 mmHg
  • BMI: < 18.5 kg/m2 or > 30 kg/m2
  • Serum potassium: < 3.5 mmol/L or > 5.5 mmol/L
  • Abnormal ECG
  • History of - cardiovascular, cancer, metabolic, respiratory, renal disease
  • Hormone replacement therapy
  • Current tobacco or nicotine use
  • Pregnant or nursing mothers
  • Major brain injury (concussions do not count)
  • Clinically diagnosed psychiatric or neurological disorder
  • Clinically diagnosed anxiety or depression
  • Psychiatric, neurological, anxiety or depression medications
  • Hypertension medications
  • Sulfonamide drug allergy
  • Contra-indications to MRI (implants, metal, etc)
  • Claustrophobia

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Salt Resistant Adults
Adults who experience minimal BP change during dietary sodium challenge
Drug: Furosemide (Diuretic)
The diuretic furosemide will be given during a 3% hypertonic saline infusion to examine blockade of the NKCC2.
Other Names:
  • Lasix
Other: Hypertonic Saline Infusion
3% Hypertonic saline infusion to acutely increase sodium and osmolality
Experimental: Salt Sensitive
Adults who experience increased BP (mean arterial pressures >5mmHg) during dietary sodium challenge
Drug: Furosemide (Diuretic)
The diuretic furosemide will be given during a 3% hypertonic saline infusion to examine blockade of the NKCC2.
Other Names:
  • Lasix
Other: Hypertonic Saline Infusion
3% Hypertonic saline infusion to acutely increase sodium and osmolality

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Bold fMRI
Time Frame: 1 hour
Intensity of sodium sensing regions of the brain
1 hour

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Blood Pressure
Time Frame: 1 hour
Systolic and Diastolic Blood pressure responses to hypertonic saline
1 hour

Other Outcome Measures

Other Outcome Measures

For clinical trials, a planned measurement described in the protocol that is used to determine the effect of an intervention/treatment on participants. For observational studies, a measurement or observation that is used to describe patterns of diseases or traits, or associations with exposures, risk factors, or treatment. Types of outcome measures include primary outcome measure and secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Sympathetic Nerve Activity
Time Frame: 1 hour
sympathetic bursts per minute
1 hour

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Delaware

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Heart, Lung, and Blood Institute (NHLBI)

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
March 5, 2024

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 1, 2028

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
July 1, 2028

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 11, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 17, 2023

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 23, 2023

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
March 24, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
March 20, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
March 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2053776
  • R01HL163906 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings