Intervention Study to Compare the Natriuretic Effects of Enalapril on Low and High Salt Diet

Salt-sensitive Hypertension Clinical Trial

— Salt  

Official title:

Paracrine Regulation of Renal Function by Dopamine in Normotensive Humans

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01324245
• Other study ID #: 2003-142
• Secondary ID: RR 17613
• Status: Completed
• Phase: N/A
• First received: March 25, 2011
• Last updated: March 25, 2011
• Start date: November 2002
• Est. completion date: May 2006

Study information

• Verified date: November 2003
• Source: Georgetown University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

The kidney plays a crucial role in maintaining salt balance by two opposing physiological mechanisms: the renal dopaminergic system which enhances salt excretion and the renin-angiotensin system (RAS) which causes salt retention. Salt-sensitive hypertension occurs when this balance is altered or abnormal. We hypothesized that this balance is influenced by salt intake: therefore dietary salt affects the natriuretic response to the renal dopaminergic agonist Fenoldopam, and the Angiotensin Converting Enzyme inhibitor, Enalapril.

In this trial we study normal salt balance mechanisms in salt resistant adults with normal blood pressure.

Description:

Eight adults of both genders and all races were studied in this double blind placebo controlled cross over study with randomization of the order of interventions. After 5 days each on low salt (about 1 gram/day) and high salt (about 6 grams/day)diet, with a washout period of at least four weeks in between, every subject was treated with Enalapril and Placebo on two consecutive days, followed by a Fenoldopam infusion for three hours, during which natriuresis and renal function testing were performed.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 45
• Est. completion date: May 2006
• Est. primary completion date: December 2005
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 55 Years

Eligibility

Inclusion Criteria:

• Volunteers

• Healthy

• Normal Blood Pressure

Exclusion Criteria:

• Renal Impairment

• Obesity

• Salt sensitive increase in blood pressure

Study Design

Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)

Related Conditions & MeSH terms

• Salt-sensitive Hypertension

Intervention

Drug:
• Fenoldopam
Intravenous infusion at 0.5 mics/Kg/min for three hours

Locations

Country	Name	City	State
United States	Georgetown University Medical Center	Washington	District of Columbia

Sponsors (2)

Lead Sponsor	Collaborator
Georgetown University	University of Virginia

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Urinary sodium excretion	All subjects received placebo/enalapril in a randomized counterbalanced fashion in both phases. Phase 1 was on low salt, while Phase 2 was on high salt. All subjects received a 3 hour fenoldopam infusion, during which time urinary sodium excretion was measured as the primary outcome bvariable.	During the trial: a 3 hour fenoldopam infusion	No
Secondary	Renal Plasma Flow	In order to explain physiologically the effects of fenoldopam on urinary sodium excretion on high and low salt diet, with and wothout enalapril, renal plasma flow was measured during the infusion using PAH clearance	During 3 hour fenoldopam infusion	No