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

This study has been completed.
Information provided by (Responsible Party):
Tommaso Gori, Johannes Gutenberg University Mainz Identifier:
First received: October 18, 2012
Last updated: March 31, 2015
Last verified: March 2015

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.

Condition Intervention
Endothelial Function
Procedure: Mental stress
Other: no intervention
Procedure: Myogenic activation
Procedure: Cold pressure test

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Basic Science
Official Title: Studies on the Physiological Meaning of Flow-mediated Constriction, Flow-mediated Dilatation and Vasomotion/Flowmotion: Circadian Variability and Role of the Sympathetic Nervous System.

Further study details as provided by Johannes Gutenberg University Mainz:

Primary Outcome Measures:
  • Change in FMD in response to sympathetic activation [ Time Frame: Change in FMD before versus 1 Minute after begin of intervention ]
    Flow-mediated dilation will be measured at rest and during each of the interventions.

Secondary Outcome Measures:
  • Change in FMC during sympathetic activation [ Time Frame: Change in FMC before versus 1 minute after begin of each intervention ]
    Change in Flow-mediated constriction induced by each of the interventions.

Enrollment: 40
Study Start Date: October 2012
Study Completion Date: March 2014
Primary Completion Date: March 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Myogenic activation
Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of myogenic activation
Procedure: Myogenic activation
A pneumatic cuff will be inflated to suprasystolic pressure around both thighs and the subjects will be asked to perform plantar flexion exercises.
Active Comparator: Cold pressure test
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
A hand will be placed in ice-cold water.
Active Comparator: mental stress
Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of mental stress
Procedure: Mental stress
Subjects will be asked to perform complex mathematic operations at a very fast pace
Active Comparator: Control
Control visit - no intervention performed - subjects will undergo endothelial function measurement twice at a distance of 45 minutes
Other: no intervention
control visit


Ages Eligible for Study:   18 Years to 40 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

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

Exclusion Criteria:

  • any active disease
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Please refer to this study by its identifier: NCT01713374

University Medical Center Mainz
Mainz, Rheinland Pfalz, Germany, 55131
Sponsors and Collaborators
Johannes Gutenberg University Mainz
Principal Investigator: Tommaso Gori, MD PhD University Medical Center Mainz
  More Information

Responsible Party: Tommaso Gori, Professor, Johannes Gutenberg University Mainz Identifier: NCT01713374     History of Changes
Other Study ID Numbers: PAN-1
Study First Received: October 18, 2012
Last Updated: March 31, 2015

Keywords provided by Johannes Gutenberg University Mainz:
endothelial function
sympathetic nervous system processed this record on May 22, 2017