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Sympathetic Nerve Activity During Hypoglycemia and Exercise

This study has been completed.
Information provided by (Responsible Party):
Steve Davis, Vanderbilt University Identifier:
First received: January 29, 2008
Last updated: June 9, 2015
Last verified: June 2015
The purpose of this study is to determine if either hypoglycemia or exercise cause differential responses in muscle and skin sympathetic nerve activity.

Condition Intervention
Diabetes Mellitus
Procedure: Hyperinsulinemic glucose clamp procedures
Procedure: moderate exercise

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Open Label
Official Title: Sympathetic Nerve Activity During Hypoglycemia and Exercise

Resource links provided by NLM:

Further study details as provided by Steve Davis, Vanderbilt University:

Primary Outcome Measures:
  • Muscle sympathetic nerve activity [ Time Frame: 2 hours ]

Enrollment: 36
Study Start Date: April 2002
Study Completion Date: July 2008
Primary Completion Date: July 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
Hyperinsulinemic euglycemic or hypoglycemic clamp with Muscle and skin sympathetic nerve activity recording in arm and/or leg
Procedure: Hyperinsulinemic glucose clamp procedures
2 hours of either euglycemic or hypoglycemic glucose clamping
Experimental: 2
Exercise with insulin or no insulin infused with muscle and skin sympathetic nerve activity measurements
Procedure: moderate exercise
90 minutes of moderate exercise with either hyperinsulinemia or euinsulinemia

Detailed Description:
The body has defensive responses to correct low blood sugar (hypoglycemia). A vital component of this response is release of glucagon and activation of the sympathetic nervous system, which provides the means for raising blood glucose levels towards normal. We can measure circulating hormones indicating the level of these responses, but additionally, sympathetic nervous system responses can be measured directly. We can measure the sympathetic nerve activity that controls blood flow to muscles (MSNA) and blood flow and sweating to skin (SSNA). The purpose of this study is to determine if either hypoglycemia or exercise cause differential responses in muscle and skin sympathetic nerve activity. We would also like to determine what the sympathetic response is to cycling exercise with insulin and normal blood sugar. Therefore, we would like to test the sympathetic responses to insulin with normal blood glucose, hypoglycemia, and during exercise bouts and normal blood glucose, with or without insulin.

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

Inclusion Criteria:

  • 36 Healthy male and female subjects (18 males and 18 females) aged 18-40 yr
  • All potential volunteers will have routine blood test to screen for hepatic, renal, and hematological abnormalities
  • Body mass index ≤30kg · m-2
  • Normal bedside autonomic function
  • Female volunteers of childbearing potential will undergo HCG pregnancy test at screening and again on the study day.

Exclusion Criteria:

  • Pregnant women
  • Subjects unable to give voluntary informed consent
  • Subjects on anticoagulant drugs or anemic
  • Subjects with a recent medical illness
  • Subjects with a history of hypertension, heart disease or cerebrovascular disease
  • Subjects with known liver or kidney disease
  • Subjects with recent weight loss or consuming a low carbohydrate diet
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Please refer to this study by its identifier: NCT00608348

United States, Tennessee
Vanderbilt University
Nashville, Tennessee, United States, 37232
Sponsors and Collaborators
Vanderbilt University
Principal Investigator: Stephen N. Davis, MD Vanderbilt University
  More Information

Responsible Party: Steve Davis, Chairman of Medicine, Vanderbilt University Identifier: NCT00608348     History of Changes
Other Study ID Numbers: IRB#020777-SNA during hypo/ex
Study First Received: January 29, 2008
Last Updated: June 9, 2015

Keywords provided by Steve Davis, Vanderbilt University:
sympathetic nerve activity

Additional relevant MeSH terms:
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases processed this record on May 25, 2017