Ch. 574 - Physiology of the Adrenal Gland

Question 1

Adrenal cortex vs medulla: Chromaffin cells

Answer 1

Medulla

Question 2

Adrenal cortex vs medulla: Derived from mesoderm

Answer 2

Cortex

Question 3

Adrenal cortex vs medulla: Derived from ectoderm

Answer 3

Medulla, neuroectoderm

Question 4

Adrenal cortex: outermost to innermost layers

Answer 4

Glomerulosa, fasciculata, reticularis

Question 5

Most potent natural mineralocorticoid in humans

Answer 5

Aldosterone

Question 6

Most potent natural glucocorticoid in humans

Answer 6

Cortisol

Question 7

Adrenal cortex vs medulla: Sustentacular cells

Answer 7

Medulla

Question 8

Hormone essential for fetal adrenal growth and maturation

Answer 8

ACTH

Question 9

Starting substrate for all steroid biosynthesis

Answer 9

Cholesterol

Question 10

Adrenal cortex can synthesize cholesterol de novo from

Answer 10

Acetate

Question 11

Provide most of the cholesterol for adrenal cortex hormone formation

Answer 11

Circulating plasma lipoproteins

Question 12

Rate-limiting step of adrenal steroidogenesis

Answer 12

Importation of cholesterol across the mitochondrial outer and inner membrane

Question 13

Glucocorticoid secretion is regulated mainly by

Answer 13

ACTH

Question 14

Pulses of ACTH and cortisol occur every ___

Answer 14

30-120 mins

Question 15

Pulses of ACTH and cortisol are highest when

Answer 15

At about the time of waking

Question 16

Pulses of ACTH and cortisol are low when

Answer 16

In the afternoon and evening

Question 17

Pulses of ACTH and cortisol reach their lowest when

Answer 17

1-2 hrs after sleep begins

Question 18

Most important stimulus for ACTH secretion

Answer 18

CRH

Question 19

Rate of aldosterone synthesis is regulated mainly by

Answer 19

RAAS and K levels

Question 20

Primary action of glucocorticoids on carb metab

Answer 20

Increases glucose by gluconeougenesis; OTHER mechanism - insulin resistance > decrease glucose entry into cells

Question 21

Glucocorticoids: Effect on fatty acid metab

Answer 21

Increasee free fatty acids

Question 22

Glucocorticoids: Protein metab

Answer 22

Catabolic or antianabolic

Question 23

Glucocorticoids: Cardiac function

Answer 23

Positive inotrope > increase in LV work index

Question 24

Glucocorticoids: Immune system

Answer 24

Generally an inhibitor; increases circulating PMNs mostly by preventing their egress from the circulation

Question 25

Most significant effect of long-term glucocorticoid excess on Ca and bone metab

Answer 25

Osteoporosis

Question 26

Major function of mineralocorticoids

Answer 26

Maintain intravascular volume by conserving Na and eliminating K and H+

Question 27

Where mineralocorticoids exert most important actions

Answer 27

DCT and cortical collecting ducts (reabsorption of Na and excretion of K

Question 28

In men ___% of biologically important androgens are derived from adrenal production, while in women ___% of androgens are adrenal in origin

Answer 28

2, 50

Question 29

Principal hormones of the adrenal medulla

Answer 29

Dopa, Epi, NE

Question 30

Measured to detect pheochromocytomas of the adrenal medulla and sympathetic NS

Answer 30

Urinary metanephrines and catecholamines

Question 31

Epi vs NE: Increases MAP

Answer 31

Both

Question 32

Epi vs NE: Increases CO

Answer 32

Epi

Question 33

Epi vs NE: Increases SBP and DBP (by increasing peripheral vascular resistance) with only a slight reduction in pulse rate

Answer 33

NE

Question 34

Epi vs NE: Decreases pulse rate and DBP (by decreasing peripheral vascular resistance)

Answer 34

Epi