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EndocrinE ` endocrine—Physiology EndocrinE ` endocrine—Physiology SEcTion iii 335
Adrenal steroids and congenital adrenal hyperplasias
ACTH Ketoconazole (blocks several steps in steroidogenesis)
Cholesterol (via StAR ) a
Anastrozole, letrozole, exemestane
Cholesterol desmolase
A
17α-hydroxylase 17,20-lyase
Pregnenolone 17-hydroxypregnenolone Dehydroepiandrosterone (DHEA)
3β-hydroxysteroid
dehydrogenase
17α-hydroxylase 17,20-lyase Aromatase
Progesterone 17-hydroxyprogesterone Androstenedione Estrone
B 21-hydroxylation
Aromatase
11-deoxycorticosterone 11-deoxycortisol Testosterone Estradiol
C C 11β-hydroxylation Metyrapone
5α-reductase
Corticosterone Cortisol Dihydrotestosterone
(DHT)
Aldosterone synthase Glycyrrhetinic acid
Aldosterone Cortisone Finasteride
Angiotensin II
ZONA GLOMERULOSA ZONA FASCICULATA ZONA RETICULARIS
Mineralocorticoids Glucocorticoids Androgens Estrogens, DHT
Adrenal cortex Peripheral tissue
a Rate-limiting step.
seX
enZyme deFiciency minerAlo corticoids [K ] bP cortisol hormones lAbs PresentAtion
+
17α-hydroxylase a androstenedione XY: ambiguous
genitalia,
undescended testes
XX: lacks 2° sexual
development
21-hydroxylase a renin activity Most common
17-hydroxy- Presents in infancy (salt
progesterone wasting) or childhood
(precocious puberty)
XX: virilization
11β-hydroxylase a aldosterone renin activity Presents in infancy
11-deoxycorti- (severe hypertension)
costerone or childhood
(results in (precocious puberty)
BP) XX: virilization
a All congenital adrenal enzyme deficiencies are autosomal recessive disorders and most are characterized by skin
hyperpigmentation (due to MSH production, which is coproduced and secreted with ACTH) and bilateral adrenal gland
enlargement (due to ACTH stimulation).
If deficient enzyme starts with 1, it causes hypertension; if deficient enzyme ends with 1, it causes virilization in females.
FAS1_2019_08-Endocrine.indd 335 11/7/19 4:30 PM
