Adrenal Gland Physiology Flashcards
What are the three zones of the adrenal cortex?
Zona Glomerulosa
Zona Fasciculata
Zona Reticularis
Where does each of the following RAAS components come from?
Renin
Angiotensinogen
Angiotensin Converting Enzyme (ACE)
Aldosterone
Renin - Kidneys
Angiotensinogen - Liver
Angiotensin Converting Enzyme (ACE) - Lungs
Aldosterone - Adrenal Cortex (Zona Glomerulosa)
What effects does Aldosterone have on Electrolytes
Increases retention of sodium and water
Decreases retention of Potassium and Hydrogen
What are some scenarios in which the Zona Glomerulosa might release more Alosterone?
Low Sodium Diet
High Potassium Intake
Hypovolemia
Hemorrhage
Trauma
What is produced by the Zona Fasciculata?
Glucocorticoids
What are the various functions of Glucocorticoids?
Metabolic Regulators of glucose, protein, and fat metabolism
Counter-acts many of insulin’s actions
Inhiubits immune and inflammatory Processes
What is produced by the Zona Reticularis?
Sex Hormones (DHEA - dehydroepiandrosterone)
What hormone controls glucocorticoid production?
ACTH - Adrenocorticotropic Hormone
What type of functional tumor originates in the Adrenal Medulla?
Pheochromocytoma
What is the main function of the Adrenal Medulla?
Secretion of Catecholamines (Epinephrine, Norepinephrine)
What type of cells make up the Adrenal Medulla?
Chromaffin Cells
What Amino-Acid is converted into Norepinephrine in the Adrenal Medulla?
Tyrosine
What is used to convert Norepinephrine into Epinephrine?
Glucocorticoids
Describe the activation of the Adrenal Medulla (including the type of nerve fibers and neurotransmitter)
Pre-ganglionic sympathetic nerve fibers release Acetylcholine. This Acetylcholine binds to the chromaffin cells which leads to the release of catecholamines.
What is the approximate half-life of catecholamines in the body?
5 Minutes
