Lecture 63 - Endocrine 5

Question 1

what organ produces adrenaline/epinephrine

Answer 1

adrenal glands

Question 2

what is the deepest and outermost structure of the adrenal gland

Answer 2

medulla; cortex

Question 3

the adrenal medulla produces

Answer 3

catecholamines (epi- and norepi-)

Question 4

the zona glomerulosa produces

Answer 4

mineralocorticoids (aldosterone) - salt regulation

Question 5

the zona fasciculata produces

Answer 5

glucocorticoids (cortisol) - sugar control

Question 6

the zona reticularis produces

Answer 6

androgens (sex hormones)

Question 7

T/F: the adrenal medulla is innervated by preganglionic sympathetic fibers

Answer 7

TRUE

Question 8

what is stimulus-secretion coupling

Answer 8

1. arrival of stimulus at cell surface receptors
2. secondary messenger system is triggered
3. release of transmitter

Question 9

describe epinephrine synthesis

Answer 9

1. tyrosine to DOPA via tyrosine hydroxylase
2. DOPA to dopamine
3. dopamine to norepinephrine
4. norepinephrine to epinephrine

Question 10

what is the rate-limiting step in epinephrine synthesis

Answer 10

tyrosine to DOPA

Question 11

what enzyme is used to convert tyrosine to DOPA

Answer 11

tyrosine hydroxylase

Question 12

describe corticosteroids (composition, receptor location, post-cell response, transport)

Answer 12

composition: cholesterol
receptor location: intracellular
post-cell response: altered gene transcription
transport: proteins

Question 13

what hormones stem from cholesterol

Answer 13

1. aldosterone
2. mineralocorticoid
3. glucocorticoid
4. androgens
5. estrogen

Question 14

what is needed for the hydroxylation of C17

Answer 14

17-alpha-hydroxylase

Question 15

T/F: cortisol is synthesized in the zona glomerulosa

Answer 15

FALSE

Question 16

adrenocortical hormones differ by a hydroxyl group on which carbon atom

Answer 16

C17

Question 17

what two events will lead to catecholamine release

Answer 17

1. stressful events (fast and large)
2. hypoglycemia

Question 18

Alpha 1 receptor does what

Answer 18

stimulatory
vasoconstriction
sm. muscle contraction

Question 19

Alpha 2 receptor does what

Answer 19

inhibitory
inhibits CNS effects and insulin release
pain-relief

Question 20

Beta 1 receptor does what

Answer 20

affects heart
increases rate and contractility

Question 21

Beta 2 receptor does what

Answer 21

affects lungs
sm. muscle relaxation
metabolic
skeletal muscle perfusion

Question 22

T/F: catecholamines interact with adrenergic receptors

Answer 22

TRUE

Question 23

A 10y/o castrated male dog presents with acute ataxia. there is a cerebellar lesion, tachycardia, and hypertension. where is the most likely place for a tumor? what hormone is being produced in excess?

Answer 23

adrenal gland; catecholamines

Question 24

T/F: hyperglycemia is a stimulus for epinephrine

Answer 24

FALSE

Question 25

what are the major effects of aldosterone

Answer 25

sodium resorption
potassium excretion
increased blood volume and blood pressure

Question 26

how does aldosterone interact with the kidney

Answer 26

stimulates sodium resorption and potassium secretion

Question 27

what are the 3 stimuli for aldosterone release

Answer 27

1. angiotensin II
2. increased plasma potassium concentrations
3. increased ACTH

Question 28

a 12y/o castrated male cat presents for severe muscle weakness (recumbent, marked ventroflexion of neck), blood potassium is severely low, and hypertension. where is the tumor most likely? what hormone is being produced in access?

Answer 28

adrenal gland; aldosterone

Question 29

which electrolyte disturbance stimulates aldosterone secretion

Answer 29

hyperkalemia (high phosphate)

Question 30

this hormone inhibits aldosterone secretion

Answer 30

ANP