Exam 2- Lecture 11

Question 1

juxtacrine signaling is _____ physical contact

Answer 1

direct

Question 2

true or false: endocrine signaling travels fairly far through the blood to a target organ

Answer 2

true

Question 3

is endocrine signaling low or high in concentration?

Answer 3

low

Question 4

is endocrine signaling a high or low affinity receptor?

Answer 4

high

Question 5

time frame for endocrine signaling

Answer 5

minutes to hours

Question 6

paracrine signaling travels a _____ distance and affects neighboring cells

a. short
b. long

Answer 6

a. short

Question 7

does paracrine signaling have a high or low local concentration?

Answer 7

high

Question 8

does synaptic signaling travel a short or far distance?

Answer 8

short (very)

Question 9

3 sex and progestational hormones to know and how many carbons?

Answer 9

progesterone (C21)
17β-estradiol (C18)
testosterone (C19)

Question 10

2 adrenocortical hormones to know and how many carbons?

Answer 10

cortisol (C21)
aldosterone (C21)

Question 11

cortisol is a glucocorticoid with what two functions?

Answer 11

anti-stress hormone, inflammation

Question 12

aldosterone is a mineralocorticoid with what two functions?

Answer 12

regulator of Na+ uptake in the kidney
raises blood volume and bp

Question 13

where are sex hormones made?

Answer 13

ovaries and testes

Question 14

when aldosterone levels are high, we have _____ sodium reuptake

a. more
b. less

Answer 14

a. more

Question 15

are steroid receptors extracellular or intracellular?

Answer 15

intracellular

Question 16

steroid receptors contain what two domains?

Answer 16

DNA-binding domain
hormone-binding domain

Question 17

when a DNA-binding domain binds to a hormone responsive element (HRE), what happens?

Answer 17

binding alters the rate of transcription

Question 18

CRH is released from where?

Answer 18

hypothalamus

Question 19

CRH stimulates release of ACTH from the (anterior/posterior) pituitary gland

Answer 19

anterior

Question 20

what is the target organ for ACTH?

Answer 20

adrenal gland

Question 21

ACTH acts on what hormone?

Answer 21

cortisol

Question 22

where is cortisol produced?

Answer 22

adrenal glands

Question 23

the first step of steroid synthesis is cholesterol to pregnenolone and is catalyzed by what enzyme?

Answer 23

p450scc (CYP11A1)

Question 24

cause of 17α-hydroxylase deficiency

Answer 24

mutations in CYP17A1, which has both 17α-hydroxylase and 17,20-lyase activities

Question 25

what enzyme deficiency is an overproduction of mineralocorticoids and deficiency of corticosteroids and sex hormones?

Answer 25

17α-hydroxylase deficiency

Question 26

3 symptoms of 17α-hydroxylase deficiency

Answer 26

-hypocortisolism -> enlargement of adrenal glands -ambiguous genitalia -hyperaldosteronism -> hypertension

Question 27

what is the minor form of congenital adrenal hyperplasia? (5%)

Answer 27

17α-hydroxylase deficiency

Question 28

what is the major form of congenital adrenal hyperplasia? (95 %)

Answer 28

21-hydroxylase deficiency

Question 29

cause of 21-hydroxylase deficiency

Answer 29

mutation in CYP21A2, which functions as 21-hydroxylase

Question 30

5 symptoms of 21-hydroxylase deficiency (slide 20)

Answer 30

-hypocortisolism -> adrenal gland enlargement -hypoaldosteronism -> hyponatremia premature androgen exposure: -ambiguous genitalia in females -hirsutism -early epiphyseal closure -> short stature

Question 31

what enzyme converts testosterone to 17β-estradiol?

Answer 31

aromatase

Question 32

2 plasma transport proteins for steroids

Answer 32

-corticoid-binding globulin (transcortin) -> glucocorticoids and progesterone -sex hormone binding globulin (SHBG) -> testosterone and estradiol

Question 33

where are steroids metabolized?

Answer 33

liver

Question 34

where are steroids excreted? (2 of them)

Answer 34

-bile (estrogen) -urine (progesterone, androgens, and glucocorticoids)

Question 35

aminoglutethimide brand name

Answer 35

Cytadren

Question 36

aminoglutethimide (Cytadren) is used to block steroid production in some hormone-dependent tumors (breast, prostate) and works by inhibiting what two enzymes?

Answer 36

aromatase, P450scc

Question 37

ketoconazole blocks the synthesis of __________ in fungi

Answer 37

ergosterol

Question 38

ketoconazole inhibits what 3 enzymes?

Answer 38

P450scc, 17α-hydroxylase, 11β-hydroxylase

Question 39

ketoconazole can treat hyperglucocorticoid stress, also known as what syndrome?

Answer 39

Cushing's syndrome