To evaluate specific markers of cardiovascular risk before and after growth hormone replacement therapy in a population of growth hormone deficient adults, as compared to an age, gender, and BMI-matched healthy population.

Growth hormone deficiency (GHD) is associated with increased cardiovascular morbidity and mortality. The effects of such a deficiency include decreased exercise capacity and tolerance, impaired cardiac function, a central fat redistribution, increased peripheral arterial resistance, and an unfavorable lipid profile. These effects have been found to be reversed with appropriate replacement therapy with recombinant human growth hormone. We plan to utilize several experimental systems to further investigate the role of growth hormone (GH) in maintaining cardiovascular health. In particular, we would like to further understand the interaction of GH with Plasminogen-activator-inhibitor-1 (a major activator of the fibrinolytic system) as well as the role of GH in the maintenance of vascular function.

Inclusion Criteria:

• Adult between the ages of 18 and 65
• Documented Growth Hormone Deficiency as defined by a peak Growth Hormone during a GHRH-Arginine Stimulation test not exceeding 9.5 ng/ml

Exclusion Criteria:

• Personal history of cardiovascular disease (previous myocardial infarction or known coronary artery disease) or diagnosis of heart disease between study visits.
• Personal history of diabetes mellitus or development of diabetes between study visits.
• Initiation of an anti-cholesterol medication or anti-hypertensive between baseline and follow-up study visit.
• Initiation of regular tobacco use between baseline and follow-up study visit.
• Pregnancy or nursing
• Current daily use of any drug known to affect the fibrinolytic system: Aspirin, Aggrenox, Plavix, Persantine, Ticlid, Pletal, Trental, Lovenox, Coumadin, Agrylin, and Hydroxyurea.

• Pfizer
• National Center for Research Resources (NCRR)