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[Melatonin reduces cortisol response to ACTH in humans]
Carmen Campino1, Francisco Valenzuela, Eugenio Arteaga
1Departamento de Endocrinología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Lira 85, S degrees piso, Santiago, Chile. ccampino@med.puc.cl
Revista Medica De Chile
|March 24, 2009
Summary
Melatonin receptors (MT1) are present in the human adrenal gland. Melatonin administration significantly reduces cortisol levels in response to ACTH stimulation, indicating a direct effect.
Area of Science:
- Endocrinology
- Molecular Biology
Background:
- Melatonin receptors are found throughout the human body, but their presence in the adrenal gland was previously unconfirmed.
- This study investigates the potential expression of melatonin receptors in the human adrenal gland.
Purpose of the Study:
- To determine if the human adrenal gland expresses melatonin receptors (MT1 and MT2).
- To evaluate the impact of melatonin on cortisol production in response to ACTH stimulation in healthy volunteers pretreated with dexamethasone.
Main Methods:
- Human adrenal glands were analyzed for MT1 and MT2 melatonin receptor mRNA expression using RT-PCR.
- A double-blind, placebo-controlled study assessed the effect of melatonin on ACTH-stimulated cortisol response in eight healthy males.
Main Results:
- MT1 melatonin receptor mRNA was detected in all four human adrenal glands analyzed.
- Melatonin significantly reduced the cortisol response to ACTH stimulation (p < 0.01) without affecting other steroid hormones.
- Melatonin also abolished the normal morning decrease in prolactin levels.
Conclusions:
- The human adrenal gland expresses the MT1 melatonin receptor.
- Melatonin directly influences the adrenal gland, reducing ACTH-stimulated cortisol production.
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