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Endocrine surgery
Published in Alexander Trevatt, Richard Boulton, Daren Francis, Nishanthan Mahesan, Take Charge! General Surgery and Urology, 2020
Ross M. Warner, Richard Boulton
The adrenal glands lie above the kidneys and are composed of a medulla and cortex, each secreting specific hormones (see Figure 16.2). The medulla releases catecholamines (adrenaline/epinephrine and noradrenaline/norepinephrine) in response to sympathetic stimulation. The cortex is divided into three parts and secretes corticosteroids in response to a hormonal stimulus: Zona glomerulosa: Secretes aldosterone (a mineralocorticoid) in response to angiotensin II (renin-angiotensin-aldosterone system).Zona fasciculata: Secretes cortisol (a glucocorticoid) in response to ACTH (adrenocorticotropic hormone) (ACTH – released from the anterior pituitary in response to hypothalamic corticotrophic-releasing hormone).Zona reticularis: Secretes androgens (sex hormones).
The endocrine system
Published in C. Simon Herrington, Muir's Textbook of Pathology, 2020
The adrenal cortex consists of three zones; from the outside inwards these are the zona glomerulosa, zona fasciculata, and zona reticularis (Figure 18.26). Each zone synthesizes a range of steroid hormones (Figure 18.27). The zona glomerulosa secretes the mineralocorticoid aldosterone, and is regulated by the renin−angiotensin system. Aldosterone is involved in the regulation of plasma volume and potassium balance. The zona fasciculata produces cortisol a glucocorticoid which have wide-ranging effects on general metabolism. The zona reticularis secretes sex steroids, mainly androgens.
Organ-specific autoimmune diseases
Published in Gabriel Virella, Medical Immunology, 2019
Gabriel Virella, George C. Tsokos
Addison's disease can either be caused by exogenous agents (e.g., infection of the adrenals by Mycobacterium tuberculosis) or be idiopathic. The idiopathic form is believed to have an autoimmune basis, since 50% of patients have been found to have antibodies to the microsomes of adrenal cells (as compared to 5% in the general population) by immunofluorescence. The autoantibodies directed against the adrenal react mainly in the zona glomerulosa, zona fasciculata, and zona reticularis and are believed to play the main pathogenic role in this disease, causing atrophy and loss of function of the adrenal cortex. Biopsy of the adrenal glands shows marked cortical atrophy with an unaltered medulla. Abundant inflammatory mononuclear cells are seen between the residual islands of epithelial cells.
An overview of dehydroepiandrosterone (EM-760) as a treatment option for genitourinary syndrome of menopause
Published in Expert Opinion on Pharmacotherapy, 2020
Michelle Holton, Chelsea Thorne, Andrew T. Goldstein
DHEA is a naturally occurring C-19 adrenal steroid derived from cholesterol and is an established precursor for the sex steroids estrogen and androgen [24]. It is secreted primarily by the zona reticularis of the adrenal cortex in humans. The secretion of DHEA is controlled by pituitary factors, most noted adrenocorticotrophin (ACTH). The adrenal cortex synthesizes DHEA daily from cholesterol and secretes 75-90% of the body’s DHEA, with the majority of the remainder being produced by the ovaries [24]. The secretion and the blood levels of the adrenal steroid dehydroepiandrosterone (DHEA) decrease profoundly with age [25,26].
Measuring stress: a review of the current cortisol and dehydroepiandrosterone (DHEA) measurement techniques and considerations for the future of mental health monitoring
Published in Stress, 2023
Tashfia Ahmed, Meha Qassem, Panicos A. Kyriacou
Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are steroid hormones that are regulated by the ACTH and possess anti-glucocorticoid properties (Gallagher & Young, 2002). DHEA is produced by the zona reticularis area in response to the ACTH. It has a regenerative role in the body, often associated with aging (Dutheil et al., 2021; Rutkowski et al., 2014). The primary function of DHEA is its involvement as a metabolic intermediate in sex hormone biosynthesis, i.e. to produce androgen and oestrogen (Mo et al., 2006). DHEA is known to improve physical well-being through reduction of total cholesterol, and prevention of bone mineral density. The steroid has an antagonistic relationship with cortisol, the primary stress hormone in humans (Gallagher & Young, 2002). This relationship can translate to reduced stress and improved psychological well-being. The cortisol-to-DHEA ratio has been considered as a precise method of assessing HPA axis functionality (Gallagher & Young, 2002). Several studies have shown an association between DHEA levels and stress intensity, as well as focusing on the cortisol/DHEA ratio. Although the magnitude of fluctuations in DHEA levels caused by stress is known to decrease with age (Dutheil et al., 2021). As a well-established biomarker of acute stress, the metabolism of DHEA and its release patterns in the human body are of great interest in stress studies. Several studies have noted that DHEA levels often appear as a peak at the end of a stressful period, and progressively return to baseline levels after recovery from stress (Dutheil et al., 2021). However, these factors are sex and age dependent therefore, it is imperative to delve deeper into the functionality of DHEA in the human body and the roles it plays within the stress response.
The vagina as source and target of androgens: implications for treatment of GSM/VVA, including DHEA
Published in Climacteric, 2023
S. Cipriani, E. Maseroli, S. A. Ravelli, L. Vignozzi
The major circulating androgens, in descending order of concentration, are DHEA sulfate (DHEAS), DHEA, androstenedione, testosterone and DHT, although only the latter two bind the androgen receptor (AR) (Table 1). Androgens are primarily produced by the ovaries, in the theca cells of developing ovarian follicles, and by the adrenal glands, in the zona reticularis of the cortex. Their synthesis is stimulated mainly by luteinizing hormone (LH) in the ovaries, and by adrenocorticotropic hormone (ACTH) in the adrenals. Depending on the tissues, they can be converted into different metabolites (Figure 1).