The Autonomic Nervous System and Obesity

• Status: Completed
• Trial end date: 2017-01-01
• Target enrollment: 0
• Participant gender: All

Summary

In its simplest terms, obesity is the results of a positive balance between food intake and energy expenditure (EE). I.e., we take in more energy, in the form of food, than we expend, e.g., by exercise. In our sedentary society, resting EE accounts for most of total energy expenditure. The sympathetic nervous system (SNS, the one that produces adrenaline) is thought to contribute to resting EE. This conclusion is based on experiments where resting EE is decreased by beta-blockers, high blood pressure medicines that block only one aspect of the sympathetic nervous system. The investigators propose to use a different approach, by using a medication called trimethaphan that produces transient withdrawal of the autonomic nervous system. The investigators will then compare the measured resting EE before and after SNS withdraw and quantify the degree of contribution to the resting EE by the SNS and delineate differences between healthy normal, healthy obese, and patients with autonomic dysfunctions.

• Phase: Phase 1
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Vanderbilt University; Vanderbilt University Medical Center
• Treatments: Ephedrine; Pseudoephedrine; Trimethaphan; Trimethaphan camsylate

Criteria

Inclusion Criteria:

• Healthy normal (BMI <= 25 Kg/m2), obese (BMI between 30 and 40)volunteers, lean hypertensive (BMI 20-28 Kg/m2), and obese hypertensive (BMI between 30 and 40)

• Ages 18-60

• Patients with pure autonomic failure and multiple system atrophy ages 18-80, referred to our service for the diagnosis and treatment of their condition, and their age sex-matched sedentary, healthy controls ages 18-80

Exclusion criteria:

• All medical students

• Pregnant women

• Heart failure, symptomatic coronary artery disease, liver impairment, history of stroke or myocardial infarction, glaucoma

• History of serious allergies or asthma

• Subjects using beta-blockers