Adrenal Medulla

Question 1

Name the Amino Acid that is the precursor of NE and E

Answer 1

Tyrosine

Question 2

Name other derivatives of Tyrosine

Answer 2

T4 and T3, dopamine

Question 3

Identify the major site of E and NE release and list some stimuli for E release

Answer 3

synthesized and secreted by Medulla of adrenal gland

Question 4

Name one disease that can affect catecholamine production

Answer 4

Pheochromocytoma; Multiple Endocrine Neoplasia

Question 5

Discuss whether E or NE is more important and why?

Answer 5

in humans/dogs E is more importatnt, because it is 80% of the catecholamine production, in cats NE is the majority.

Question 6

Effect of epinephrine/norepinephrine on: carbohydrate metabolism

Answer 6

increased, Increases blood glucose

Question 7

Effect of epinephrine/norepinephrine on: the cardiovascular system

Answer 7

dilates skeletal blood vessels

Question 8

Effect of epinephrine/norepinephrine on: the gut:

Answer 8

constricts blood vessels, decreases motility

Question 9

Effect of epinephrine/norepinephrine on: lipid metabolism

Answer 9

increased lipolysis

Question 10

Effect of epinephrine/norepinephrine on: skeletal muscle metabolism:

Answer 10

increased strength of contraction

Question 11

Lists the effects of epinephrine/norepinephrine throughout the body

Answer 11

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

Question 12

Define: Epinephrine

Answer 12

aka Adrenaline; major catecholamine in humans/dogs, secreted by the Medulla of adrenal gland

Question 13

Define: Norepinephrine

Answer 13

major catecholamine in cats; has similar actions to epinephrine

Question 14

Define: Catecholamines

Answer 14

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.

Question 15

Define: Adrenal Medulla

Answer 15

site of catecholamine synthesis, storage, and release

Question 16

Define: Hypoglycemia

Answer 16

can stimulate catecholamine release and typical E/NE responses

Question 17

Define: Pheochromocytoma

Answer 17

common in older dogs, chromaffin cell tumor resulting in excess levels of catecholamines

Question 18

Define: Multiple Endocrine Neoplasia

Answer 18

autonomous and excess secretion of more than one hormone; similar syndrome seen in humans; autosomal dominant trait

Question 19

Define: Chromaffin cells

Answer 19

neuroendocrine cells found in the medulla of the adrenal glands

Question 20

Define: Pheochromocytoma

Answer 20

chromaffin cell tumor, excess levels of catecholamines, often but not always malignant, most common in older dogs

Question 21

Define: tachycardia

Answer 21

increased heart rate

Question 22

Define: hypertension

Answer 22

high blood pressure