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Abnormal vascular reactivity in growth hormone deficiency
B Capaldo1, V Guardasole, F Pardo
1Departments of Internal Medicine and Cardiovascular Sciences and of Endocrinology, University Federico II, Naples, Italy.
Circulation
|February 7, 2001
Summary
Growth hormone (GH) deficiency impairs vascular reactivity in patients, contributing to cardiovascular risk. GH replacement therapy restores normal vascular function, highlighting GH's crucial role in maintaining cardiovascular health.
Area of Science:
- Cardiovascular Physiology
- Endocrinology
- Vascular Biology
Background:
- Patients with growth hormone (GH) deficiency (GHD) face increased cardiovascular mortality.
- Vascular reactivity's role in GHD-related arteriosclerosis is not well understood.
Purpose of the Study:
- To investigate vascular function and reactivity in patients with childhood-onset GHD.
- To determine if GH replacement therapy normalizes vascular function in GHD patients.
Main Methods:
- Strain gauge plethysmography was used to measure forearm blood flow response to vasodilators.
- Vascular reactivity was assessed using endothelium-dependent (acetylcholine) and independent (sodium nitroprusside) agents.
- Forearm nitrite and cGMP release, and peak hyperemic response to ischemia were measured.
Main Results:
- Untreated GHD patients showed significantly reduced forearm blood flow response to acetylcholine and sodium nitroprusside.
- Nitrite and cGMP release during acetylcholine stimulation was lower in untreated GHD patients.
- GH replacement therapy normalized vascular reactivity and hyperemic response to ischemia in GHD patients.
Conclusions:
- GH is essential for maintaining normal vascular function in humans.
- Impaired vascular reactivity in GHD contributes to increased cardiovascular risk.
- GH therapy can restore vascular function in GHD patients.
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