PATHOPHYSIOLOGY OF ADRENOCORTICAL HORMONE Dr. AmelEassawi
Objectives At the end of this lecture the student should be able to: • Describe Pathophysiology of hypo and hyperpadrenalism. • Correlate the features of hypo and hyper adrenalism with the physiological action and control mechanism of adrenocortical hormones. • Describe the different stress mechanisms and the body’s response to these stressors.
Pathophysiology • Primary hyperaldosteronism, or Conn’s syndrome)-Adrenal tumor. • Secondary hyperaldosteronism- inappropriately high activity of the renin-angiotensin-aldosterone system. • Cortisol hypersecretion - (Cushing’s syndrome). • Adrenal androgen hypersecretion – adrenogenital syndrome.
HYPERALDOSTERONISM • Primary hyperaldosteronism, or Conn’s syndrome • Cause: • Adrenal tumor of aldosterone –secreting cells • Secondary hyperaldosteronism • Cause: • inappropriately high activity of the renin-angiotensin-aldosterone system. Symptoms: • excessive Na+ retention (hypernatremia) and • K +depletion (hypokalemia). • high blood pressure (hypertension)
CUSHING’S SYNDROME • Cause • Overstimulation of the adrenal cortex by excessive amounts of CRH and/or ACTH, • Adrenal tumors that uncontrollably secrete cortisol independent of ACTH, • ACTH-secreting tumors located in places other than the pituitary, most commonly in the lung
CUSHING’S SYNDROME • Features • High blood glucose • Glucosuria – Adrenal diabetes • Protein shortage • Buffalo hump • Moon face • Thin extremities, weakness & fatigue • Reddish – purple linear stria
CUSHING’S SYNDROME Before After
ADRENAL ANDROGEN HYPERSECRETION • Adrenogenital syndrome • In adult females • Male pattern of body hair • Deep voice • Muscular arms & leg • Decrease breast size, menstrual suppression
ADRENAL ANDROGEN HYPERSECRETION • Adrenogenital syndrome • In newborn females • Male type of external genitalia • female pseudohermaphroditism • In pubertal males • prematurely develop male secondary sexual characteristics • precocious pseudopuberty • In adult males • No apparent effect
ADRENOCORTICAL INSUFFICIENCY • Primary adrenocortical insufficiency, also known as Addison’s disease • Autoimmune destruction of cortex • Features are related to Aldosterone deficiency • K+retention (hyperkalemia), • Na+depletion (hyponatremia), • disturbed cardiac rhythm. • Hypotension • Features are related to cortisol deficiency • poor response to stress, • hypoglycemia (low blood glucose) • hyperpigmentation (darkening of the skin)
References • Human physiology, Lauralee Sherwood, seventh edition. • Text book physiology by Guyton &Hall,11th edition. • Text book of physiology by Linda .S .Costanzo third edition