Physiological Assessment of the Endothelium - Circadian Rhythm and Role of the Sympathetic Nervous System

NCT01713374 | Completed

• 1 other identifier: PAN-1
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to determine whether interventions aimed at increasing sympathetic tone modify endothelial function measures as assessed by the measurement of flow-mediated dilation (FMD) and constriction (FMC). The investigators hypothesize that the three interventions under study will increase FMC while causing a blunting in FMD. Further, the investigators plan to study the circadian variability of FMC and FMD. The investigators hypothesize a peak of FMD in the late hours of the day and a peak of FMC in the early hours.

Conditions

Endothelial Function

Keywords

endothelial function; sympathetic nervous system

Outcome Measures

Primary Outcomes (1)

• Change in FMD in response to sympathetic activation

  Flow-mediated dilation will be measured at rest and during each of the interventions.

  Change in FMD before versus 1 Minute after begin of intervention

Secondary Outcomes (1)

• Change in FMC during sympathetic activation

  Change in FMC before versus 1 minute after begin of each intervention

Study Arms (4)

Myogenic activation

ACTIVE COMPARATOR

Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of myogenic activation

Procedure: Myogenic activation

Cold pressure test

ACTIVE COMPARATOR

Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of cold pressure test

Procedure: Cold pressure test

mental stress

ACTIVE COMPARATOR

Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of mental stress

Procedure: Mental stress

Control

ACTIVE COMPARATOR

Control visit - no intervention performed - subjects will undergo endothelial function measurement twice at a distance of 45 minutes

Other: no intervention

Interventions

Mental stress PROCEDURE

Subjects will be asked to perform complex mathematic operations at a very fast pace

mental stress

no intervention OTHER

control visit

Control

Myogenic activation PROCEDURE

A pneumatic cuff will be inflated to suprasystolic pressure around both thighs and the subjects will be asked to perform plantar flexion exercises.

Myogenic activation

Cold pressure test PROCEDURE

A hand will be placed in ice-cold water.

Cold pressure test

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• healthy volunteers with no cardiovascular risk factor, no current disease, normal laboratory parameters and ECG.

You may not qualify if:

• any active disease

Sponsors & Collaborators

• Johannes Gutenberg University Mainz: lead

Study Sites (1)

University Medical Center Mainz

Mainz, Rhineland-Palatinate, 55131, Germany

Location

Study Officials

• Tommaso Gori, MD PhD

  University Medical Center Mainz

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: October 18, 2012
• First Posted: October 24, 2012
• Study Start: October 1, 2012
• Primary Completion: March 1, 2013
• Study Completion: March 1, 2014
• Last Updated: April 1, 2015

Record last verified: 2015-03

Locations

DE (1)