Study of the Effect of Growth Hormone-Releasing Hormone Antagonist on Growth Hormone Release in Acromegaly
OBJECTIVES: I. Determine whether release of endogenous growth hormone (GH)-releasing hormone is involved in GH responses to clonidine, pyridostigmine, levodopa, arginine, GH-releasing peptide, insulin-induced hypoglycemia, and exercise in patients with acromegaly.
II. Determine whether endogenous GH-releasing hormone influences the maintenance of GH hypersecretion.
|Study Design:||Primary Purpose: Screening|
|Study Start Date:||May 1993|
PROTOCOL OUTLINE: Growth hormone-releasing hormone antagonist (GHRH-A) is administered to volunteers and followed with 1 of these challenges: insulin, clonidine, pyridostigmine, arginine, levodopa, growth hormone-releasing peptide, or exercise. Tests are repeated with normal saline as the control; the order of administration (control vs. pharmacologic stimulation) is randomly assigned.
Patients receive GHRH-A (dose determined in volunteer study), thyrotropin-releasing hormone, and growth-releasing hormone.
All stimulation tests follow an overnight fast.
|Study Chair:||Ariel Barban||University of Michigan|