PCOL 838A: DISORDERS OF THE ADRENAL CORTEX

What are the histologic layers of the adrenal cortex? zona glomerulus, zona fasciculata, zona reticularis What hormone does the zona glomerulus secrete? aldosterone What hormone does the zona fasciculata secrete? cortisol What hormone does the zona reticularis secrete? DHEA What triggers glucocorticoid secretion? corticotropin-releasing hormone (CRH) + ACTH --> cortisol What causes negative feedback control of the hypothalamic-pituitary-adrenal axis? cortisol Describe the diurnal rhythm of ACTH secretion. levels of ACTH and glucocorticoid rises in the morning before awakening, chronic stress may lead to dysregulation of the feedback loop leading to a failure of the circadian machinery with possible sleep/metabolic disturbances What conditions alter the diurnal rhythm of ACTH secretion? Cushing's syndrome, mood disorders, Alzheimer's disease, and metabolic syndrome Describe the major physiologic effects of glucocorticoids. - anti-inflammatory response - net loss of amino acids - gluconeogenesis - glycogen synthesis - lipoly