Adrenal Medulla Flashcards
Name the Amino Acid that is the precursor of NE and E
Tyrosine
Name other derivatives of Tyrosine
T4 and T3, dopamine
Identify the major site of E and NE release and list some stimuli for E release
synthesized and secreted by Medulla of adrenal gland
Name one disease that can affect catecholamine production
Pheochromocytoma; Multiple Endocrine Neoplasia
Discuss whether E or NE is more important and why?
in humans/dogs E is more importatnt, because it is 80% of the catecholamine production, in cats NE is the majority.
Effect of epinephrine/norepinephrine on: carbohydrate metabolism
increased, Increases blood glucose
Effect of epinephrine/norepinephrine on: the cardiovascular system
dilates skeletal blood vessels
Effect of epinephrine/norepinephrine on: the gut:
constricts blood vessels, decreases motility
Effect of epinephrine/norepinephrine on: lipid metabolism
increased lipolysis
Effect of epinephrine/norepinephrine on: skeletal muscle metabolism:
increased strength of contraction
Lists the effects of epinephrine/norepinephrine throughout the body
Free Fatty Acids: Increased Skeletal Muscle: Contracts Harder Gylcogenolysis:: Increased Erythropoietin Increased Glucagon: Increased Thyroid Hormone: Increased Multiple Endocrine Neoplasia Chromaffin Cell: Site of NE and E storage in medulla, contain chromagranin protein bound to the hormone Tachycardia: Increased heart rate Hypertension Increased BP
Define: Epinephrine
aka Adrenaline; major catecholamine in humans/dogs, secreted by the Medulla of adrenal gland
Define: Norepinephrine
major catecholamine in cats; has similar actions to epinephrine
Define: Catecholamines
E & NE, hormones released from medulla of adrenal gland which are released IMMEDIATELY upon stimulation to bind to membrane receptors. Broken down in neural tissue, liver, kidneys.
Define: Adrenal Medulla
site of catecholamine synthesis, storage, and release
Define: Hypoglycemia
can stimulate catecholamine release and typical E/NE responses
Define: Pheochromocytoma
common in older dogs, chromaffin cell tumor resulting in excess levels of catecholamines
Define: Multiple Endocrine Neoplasia
autonomous and excess secretion of more than one hormone; similar syndrome seen in humans; autosomal dominant trait
Define: Chromaffin cells
neuroendocrine cells found in the medulla of the adrenal glands
Define: Pheochromocytoma
chromaffin cell tumor, excess levels of catecholamines, often but not always malignant, most common in older dogs
Define: tachycardia
increased heart rate
Define: hypertension
high blood pressure
