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

Not Applicable

Completed

• Conditions: Endothelial Function
• Interventions: Procedure: Myogenic activation; Procedure: Cold pressure test; Other: no intervention; Procedure: Mental stress

• Registration Number: NCT01713374
• Lead Sponsor: Johannes Gutenberg University Mainz

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.

Detailed Description

Not available

Study Timeline

• Study Start: 2012-10
• Study First Submitted: 2012-10-18
• Study First Submitted QC: 2012-10-22
• Study First Posted: 2012-10-24
• Primary Completion: 2013-03
• Study Completion: 2014-03
• Status Verified: 2015-03
• Last Update Submitted: 2015-03-31
• Last Update Posted: 2015-04-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 40

Inclusion Criteria

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

Exclusion Criteria

• any active disease

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Myogenic activation	Myogenic activation	Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of myogenic activation
Cold pressure test	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
Control	no intervention	Control visit - no intervention performed - subjects will undergo endothelial function measurement twice at a distance of 45 minutes
mental stress	Mental stress	Subjects will undergo endothelial function assessment at rest and, after a 45 minutes pause, 1 minute after begin of mental stress

Primary Outcome Measures

Name	Time	Method
Change in FMD in response to sympathetic activation	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

Name	Time	Method
Change in FMC during sympathetic activation	Change in FMC before versus 1 minute after begin of each intervention	Change in Flow-mediated constriction induced by each of the interventions.

Trial Locations

Locations (1)

University Medical Center Mainz; 🇩🇪 Mainz, Rheinland Pfalz, Germany