Cholesterol and Steroids

Question 1

Hypercholesterolemia

Answer 1

cholesterol=a portion of bile.

cholestyramine: bile acid sequestrant. reduce plasma cholesterol. promotes excretion of bile. increases bile acid synth which consumes cholesterol (precursor). increase 7a-hydroxylase.

Question 2

Bile Salt deficiency.

Answer 2

…leading to too much cholesterol in gallbladder. Cholelithiasis (cholesterol gallstones) due to not enough bile acid to sequester cholesterol.

chenodeoxycholic acid pills: bile acid ills to dissolve gallstones (takes months to years).
laparoscopic cholecystectomy.

Question 3

3-B-HSD def

Answer 3

no glucocorticoids, mineralcorticoids, androgens, or estrogens

too little salt retention (salt wasting/Na+ excretion) from too little mineralcorticoid/aldosterone. ambiguous genitalia from too little androgens. no hypertension (caused by too much mineralcorticoid)

Question 4

ER+ Breast Cancer

Answer 4

Aromatase produces estrogen.

premenopausal (express estrogens): Tamoxifen. may cause uterine cancer

postmenopausal (low estrogen): Aromatase inhibitor. block estrogen production.

Question 5

Primary Aldosteronism

Answer 5

excessive aldosterone. adrenal cortex hyperplasia/tumor. too much Na+ and water retention from too much aldosterone. hypertension.

Question 6

17ahydroxylase def

Answer 6

increased mineralcorticoid. increased fluid retention, hypertension

Question 7

21ahydroxylase def

Answer 7

increased androgens (masculiation of female genitalia, early virilization males)

Question 8

11ahydroxylase def

Answer 8

increased mineralcorticoid (deoxycorticosterone) (fluid retention, hypertension). increased androgens (masculinization and virilization)

Question 9

Calcitriol (Vit D3) def

Answer 9

rickets in children. osteomalacia in adults. Calcitriol (derived from 7DHC, immediate precursor to cholesterol) mobilizes Ca++ from bone.

increase sun exposure. vit D supplements