MedPath

Dopamine in Orthostatic Tolerance

Not Applicable
Terminated
Conditions
Postural Tachycardia Syndrome
Registration Number
NCT00748228
Lead Sponsor
Vanderbilt University
Brief Summary

One goal of this study is to determine whether people with different amounts of dopamine-beta-hydroxylase (DBH) have different responses to events that affect blood pressure and heart rate. We will also study whether increasing dietary salt improves symptoms during upright posture. Finally, we will examine whether the dietary sodium level influences serum DBH activity and whether DBH level influences the response to sodium. DBH levels and the function of the sympathetic or involuntary nervous system will be assessed in normal volunteers and in patients with postural tachycardia syndrome (POTS).

Detailed Description

Not available

Recruitment & Eligibility

Status
TERMINATED
Sex
All
Target Recruitment
22
Inclusion Criteria
  • Upright plasma norepinephrine > 600 pg/ml, or
  • An increase in heart rate of > 30 beats per minute upon standing, and
  • Withdrawal of all medications for at least 3 days, and
  • No associated medical illness, and
  • Age 18 - 60 years old.
Exclusion Criteria
  • Older than 60 years of age
  • Routinely taking medications affecting the autonomic nervous system
  • Any chronic illness (cardiac, pulmonary, endocrine, gastrointestinal, rheumatologic) other than POTS
  • Anemia (Hct < 30)
  • Women of childbearing age who are pregnant or nursing
  • Unable to give informed consent

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Primary Outcome Measures
NameTimeMethod
plasma dopamine-beta-hydroxylaseat enrollment and after tests
plasma dopamineafter tests
Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Vanderbilt University

🇺🇸

Nashville, Tennessee, United States

Vanderbilt University
🇺🇸Nashville, Tennessee, United States

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