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Normal and abnormal function of the hypothalamic-pituitary-adrenocortical system in man
Endocrine Reviews
|January 1, 1984
Summary
This study reviews methods for assessing hypothalamic-pituitary-adrenocortical (HPA) axis function and establishes normal response limits. These limits helped evaluate HPA function in 158 patients, identifying abnormalities in 70.
Area of Science:
- Endocrinology
- Neuroendocrinology
- Human Physiology
Background:
- The hypothalamic-pituitary-adrenocortical (HPA) axis regulates the body's response to stress.
- Accurate assessment of HPA axis function is crucial for diagnosing endocrine disorders.
- Published methods for evaluating HPA activity have varied, necessitating standardization.
Purpose of the Study:
- To review existing methods for measuring HPA axis activity.
- To establish normative ranges for standard and modified HPA function tests.
- To assess HPA axis function in patients with suspected or confirmed HPA disorders.
Main Methods:
- Review of published literature on HPA axis testing methods.
- Establishment of normal limits for basal cortisol, metyrapone response, and stress tests (hypoglycemia, ACTH).
- Evaluation of HPA function in 158 patients using defined normative data.
Main Results:
- Normal circadian and postprandial cortisol levels were defined (6.2 ± 0.3 SEM μg/dl).
- Metyrapone administration significantly increased urinary 17-OHCS excretion (1.7–7.8 times basal).
- A cortisol/glucose response index (0.20–0.87 μg/mg) reliably indicated normal response to hypoglycemic stress.
Conclusions:
- Defined normative values provide a reliable basis for assessing HPA axis function.
- HPA axis function was found to be normal in 88 of 158 patients evaluated.
- Abnormal HPA function was identified in 70 patients with pituitary tumors or related conditions.
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