Biochem 2-13 Steroidogenesis

Front 1

Where is the adrenal gland located at?

Back 1

The adrenal glands lies in the retroperitoneum above or medial to the upper poles of the kidneys

Front 2

What are the three zones of the adrenal gland?

Back 2

The zona glomerulosa, zona fasciculata and zona reticularis.

Front 3

The zona fasciculata produces:

Back 3

cortisol and androgens

Front 4

Which zones does ACTH regulate?

Back 4

ACTH primarily regulates the zona fasciculata and the zona reticularis.

Front 5

What is the precursor for all the steroids?

Back 5

cholesterol

Front 6

Mutations within StAR are linked to:

Back 6

congenital lipid adrenal hyperplasia

Front 7

ACTH regulates:

Back 7

Cortisol synthesis

Front 8

(True or False) Glucocorticoids maintain or raise blood glucose.

Back 8

True

Front 9

The enzyme responsible for the conversion of Pregnenolone to Progesterone is:

Back 9

3-beta-HSD (3-beta-hydroxysteroid dehydrogenase)

Front 10

The enzme responsible for the conversion of Pregnenolone to DHEA is:

Back 10

CYP17 (17-hydroxylase)

Front 11

zona glomerulosa

Back 11

receptors for Ang II/K+; CYP11B2→aldosterone

Front 12

zona fasiculata

Back 12

receptors for ACTH, CYP11B1 & CYP17→cortisol

Front 13

The zona glomerulosa produces:

Back 13

Aldosterone

Front 14

zone reticularis

Back 14

CYP17→DHEA

Front 15

Addison's disease

Back 15

Phyicial Findings:
Low blood pressure(orthostatis hypotension), hyperpigmentation of the skin, and Goiter's. Additional findings are hypoglycemia, hyponatreamia, and hyperkalemia.

Front 16

StAR protein

Back 16

Controls mitochondrial cholesterol import; controlled by ACTH in the adrenal gland and within the testis by hCG during the first trimester and LH later in Pregnancy.

Front 17

ACTH

Back 17

induces the adrenal cortex to synthesize glucocorticoids, mineral corticoids and the androgen precursor dehydroepiandrosterone (DHEA)

Front 18

Congenital Adrenal Hyperplasia

Back 18

Physical Findings:
ambiguous genitalia
vomiting
hypothermic
malnourished
Dehydration
Low blood pressure
Hyponatremia
Hyperkalemia
& Hypochloremia

Front 19

Rate limiting step in steroidogenesis:

Back 19

CYP11A1; cholesterol→pregnenolone

Front 20

What is the primary site of steroid synthesis.

Back 20

Adrenal cortex, ovaries, testes, and ovarian corpus luteum.

Front 21

What organs are involved in vitamin D synthesis?

Back 21

skin, liver and kidney

Front 22

Overproduction of ACTH can induce _____, hypertrophy of the inner zones of the adrenal cortex.

Back 22

hyperplasia

Front 23

Cholesterol is transported into mitochondria through the __________ transporter.

Back 23

StAR (steroidogenic acute regulatory protein)

Front 24

Can we synthetize vitamin D?

Back 24

YES

Front 25

Glucocorticoids (cortisol) stimulate hepaitc ____, prolong the effects of ____ & ____, and suppress the _____.

Back 25

GNG, glucagon & epinephrine, immune system.

Front 26

Do glucocorticoids increase or decrease expression of PEPCK?

Back 26

increase

Front 27

What regulates Vitamin D synthesis?

Back 27

PTH-parathryoid hormone

Front 28

Do glucocorticoids increase or decrease expression of G-6-phosphatase?

Back 28

increase

Front 29

Adrenal Androgen synthesis occurs in the zona _____ of the adrenal cortex

Back 29

reticularis

Front 30

Do glucocorticoids increase or decrease glucose uptake?

Back 30

decrease

Front 31

Ricket's disease

Back 31

A deficiency of vitamin D in children. Patient's commonly present with "bowing" of the legs, hypocalcemia, neuromuscular irritability, convulsions, tetany, and paresthesias.

Front 32

The enzyme responsible for the conversion of cholesterol to Pregnenolone is:

Back 32

CYP11A

Front 33

Do glucocorticoids increase or decrease expression of leptin?

Back 33

decrease

Front 34

The majority of the cholesterol used for steorid synthesis is obtained:

Back 34

from LDL

Front 35

Do glucocorticoids increase or decrease expression of PTH? Vitamin D?

Back 35

increase, increase

Front 36

Addison's Disease

Back 36

cortisol deficiency; Generalized hyperpigmentation of skin and mucous membranes + Weakness, Fatigue, Weight Loss, Anorexia, and GI disturbances

Front 37

The rate limiting step in steroid synthesis is:

Back 37

CYP11A

Front 38

The enzyme responsible for the conversion of testosterone to Estradiol is:

Back 38

Aromatase

Front 39

Cortisol Pathway:

Back 39

cholesterol→pregnenolone→progesterone→17 a-hydroxyprogesterone→Cortisol

Front 40

Stress is responsible for activating or inhibiting the HPA axis

Back 40

Activating

Front 41

Which CYPs get you from progesterone to aldosterone?

Back 41

CYP21, CYP11B1, CYP11B2

Front 42

The rate limiting step in the steroid synthesis pathway is:

Back 42

CYP11A

Front 43

The synthesis of aldosterone is regulated by:

Back 43

Renin/Angiotensis pathway
Na/K
ACTH
& Dopamine

Front 44

Aldosterone acts on the _____ to cause sodium retention of Sodium and excretion of K+ and H+

Back 44

distal and collecting tubules

Front 45

mineralocorticoids are produced in the zona _____

Back 45

glomerulosa

Front 46

The rate limiting step in the synthesis of sex steroids is:

Back 46

CYP11A (cholesterol to pregneolone)

Front 47

Aldosterone Overexpression (primary aldosteronism)

Back 47

↑ Plasma and ECF volume;
↑ Na+ and H2O retention;
↑ cardiac output;
Renal K+ wasting ↑
hypertension, hypokalemia, and inhibition of renin-angiotensin system

Front 48

mineralocorticoid deficiency

Back 48

Renal Sodium Wasting
Potassium Retention
Dehydration
Hypotension
Hyponatremia
Hyperkalemia
Acidosis

Front 49

Adrogens Pathway:

Back 49

cholesterol→pregnenolone→17 a-hydroxypregnenolone→DHEA→Androstenedione

Front 50

_____, _____ and _____ function primarily as precursors for peripheral conversion to the active androgenic hormones testosterone and dihydrotestosterone.

Back 50

Androstenedione, DHEA and DHEA sulfate

Front 51

Does adrenal androgen production play a greater role in men or women?

Back 51

women; only 5% of androgens produced in the adrenal glands in men.

Front 52

Problems in andrenal androgen production in females results in:

Back 52

Cushing syndrome, adrenal carcinoma or congenital adrenal hyperplasia

Front 53

LH stimulates testosterone synthesis in the _____ cells of the human testicle; the testosterone diffuses into _____ cells to assist in maturation of the spermatozoa

Back 53

Leydig, Sertoli

Front 54

_____ converts testosterone to estradiol

Back 54

Aromatase

Front 55

Theca Cells-Secrete primarily _____;
Stromal Cells-Secrete primarily _____;
Granulosa Cells-Secrete primarily _____;
Corpus Luteum-Secrete _____.

Back 55

androgens, androgens, estrogens, progesterone; Regulation is achieved by follicle-stimulating hormone (anterior pituitary gland) through the activity of Aromatase.

Front 56

17-β-HSD

Back 56

androstenedione→testosterone

Front 57

in the absence of DHEA, androstenedione can be produced from _____.

Back 57

17 α-hydroxyprogesterone

Front 58

T/F: 17 α-hydroxyprogesterone can be produced from 17 α-hydroxypregnenolone.

Back 58

true

Front 59

adrenal medulla produces_____

Back 59

catecholemines