Intro to Endocrine Flashcards
What does the Adrenal Medulla secrete?
Catecholamines: Epinephrine, norepinephrine, and dopamine
What are catecholamines released in response to and what do they cause?
Stress. They increase vasoconstriction (raise B/P), intensify HR and CO, increase ciliary muscle contraction (dilate pupils), stimulate lipolysis and glycogneolysis for energy production, and decrease intestinal motility.
What does the Adrenal Cortex secrete?
Steroid hormones. Mineralcorticoids(Aldosterone), Glucocorticoids (Cortisol), and Gonadocorticoids.
What is Aldosterone’s function?
Regulates sodium and potassium in extracellular fluids. Retains sodium ions and water by kidneys. Increases blood VL and BP. Is necessary for life.
What is Cortisol’s function?
Increases and maintains glucose concentrations in blood by protein and fat being broken down and converted to glucose, and exerts potent anti-inflammatory and immunosuppressive effects on the body.
What do Beta cells in the pancreas produce?
Insulin and Amylin
What is Insulin’s function?
Promotes storage of ingested nutrients by binding to receptor on surface of target cell to promote storage. Stimulates formation of glycogen)
What is Amylin’s function?
Inhibits the appearance of glucose in the plasma by slowing gastric empyting, reducing appetite, and inhibiting secretion of glucagon.
What do Alpha cells in the pancreas produce?
Glucagon and Somatostatin (pretty sure Somatostatin is produced by Delta cells, but his slides say otherwise)
What is Glucagon’s function?
Makes energy available to tissues by stimulating breakdown of glycogen.
What is the function of Somatostatin?
Inhibits Growth Hormone, Insulin and Glucagon
What are PP cells?
Pancreatic Polypeptide. Self regulation of the pancreas (endo and exocrine)
What hormones do the ovaries produce?
estrogen, progesterone, and androgens.
What effect does testosterone have on the blood?
Stimulates erythropoesis. An increase in testosterone will increase erythropoiesis which makes the blood more viscous.
Explain the positive feedback loop of Oxytocin in labor.
Oxytocin stimulates the uterus to contract and stimulates the placenta to make prostaglandins which sends positive feedback to the pituitary to release more oxytocin, which thereby stimulate more contractions of the uterus
Circhoral
Episodic release of about an hour
Ultradian
Episodic release longer than an hour but less than 24hrs
Circadian
Episodic release approximately every 24hrs
Diurnal
Episodic activity is expressed at defined periods of the day
Circatrigintan
Episodic release approximately every 30 days
Free Hormone
fraction available for binding to receptors; the active hormone; dictates magnitude of feedback inhibition that controls hormone release; fraction that is cleared from circulation; correlates best with clinical states or hormone excess/deficiency.
Chemical Messenger
Travel to and affect target tissues by binding to specific receptors. Modify target tissue activity and elicit physiological response.
When are stimulation tests used?
When hypofunction is suspected. They are designed to test the glands ability to secrete hormone. (Ex- ACTH Stim test= give artificial ACTH and test blood cortisol)
When are Suppression tests used?
When hyperfunction is suspected. (Ex: Dexamethasone (syn. cortisol) Sup. test- examines blood and urine for presence of cortisol.
