Related Experiment Videos
Serum cortisol and dehydroepiandrosterone sulfate responses to adrenocorticotropin stimulation in premature infants
Insights
Premature infants show higher basal cortisol and dehydroepiandrosterone sulfate (DHAS) levels early on. Their adrenal response to ACTH stimulation matures by 4 weeks, with a decreasing DHAS to cortisol ratio.
Area of Science:
- Neonatology
- Endocrinology
- Pediatric Physiology
Background:
- Premature infants exhibit unique physiological characteristics.
- Adrenal gland function and steroidogenesis are critical in early development.
- Understanding steroid hormone dynamics in neonates is essential for assessing health and development.
Purpose of the Study:
- To investigate the serial changes in adrenal steroid hormone production in premature infants.
- To assess the adrenal response to ACTH stimulation at different neonatal ages.
- To evaluate the relationship between cortisol and dehydroepiandrosterone sulfate (DHAS) production and their response to ACTH.
Main Methods:
- Serial ACTH stimulation tests were conducted on 15 premature infants at 5-10 days and 27-31 days of age.
- Serum cortisol and DHAS levels were measured pre- and post-ACTH stimulation using radioimmunoassay.
- Statistical analysis compared hormone levels and responses across different age points.
Main Results:
- Basal cortisol and DHAS levels were significantly higher in the 5-10 day period compared to the 27-31 day period.
- The net increase in cortisol after ACTH stimulation (delta cortisol) significantly increased with age.
- While delta DHAS did not change significantly, the ratio of delta DHAS to delta cortisol decreased with age, indicating a relative shift in steroidogenesis.
Conclusions:
- The adrenal glands of premature infants show maturational changes in response to ACTH stimulation within the first month of life.
- Cortisol production capacity increases, while the relative contribution of DHAS to the overall adrenal response changes.
- These findings highlight the dynamic nature of adrenal function during early neonatal development.
Abstract:
ACTH stimulation tests were performed in 15 premature infants in a serial fashion at the ages of 5--10 days and 27--31 days. Six of the 15 had subsequent ACTH stimulation tests at 6--8 weeks and/or 12--13 weeks. The pre- and post-ACTH serum cortisol and dehydroepiandrosterone sulfate (DHAS) levels were determined by radioimmunoassay. The mean basal levels of cortisol, 55 ng/ml, and DHAS, 4108 ng/ml, were significantly higher (P less than 0.05 and P less than 0.025, respectively) at 5--10 days than those of 24 ng/ml and 1858 ng/ml, respectively, at 27--31 days. The mean net change (delta) of cortisol after ACTH at 5--10 days, 95 ng/ml, increased significantly to 148 ng/ml at 27--31 days. However, deltaDHAS did not differ significantly between the two periods (1514 ng/ml vs. 972 ng/ml). Therefore, deltaDHAS/deltacortisol was lower (P less than 0.05) at 27--31 days than at 5--10 days. No further significant changes were observed after 4 weeks of age in the levels of the two steroids. There was little correlation of basal levels between cortisol and DHAS, nor between deltacortisol and deltaDHAS at any age period we studied. There were four infants whose mothers had prenatal steroid treatment for the prevention of hyaline membrane disease and their values were not different from the other infants.