Exam 2: Lecture X, Androgens

Question 1

In men, LH and FSH control….

Answer 1

test secretion and sperm production

secreted by AP gland

Question 2

LH stimulate Leydig cells which…..

Answer 2

secrete test at start of puberty

Question 3

FSH stimulates Sertoli cells which….

Answer 3

produce sperm

Question 4

Testosterone

Answer 4

main natural androgen

steroid hormone, precursor is cholesterol

Question 5

Testosterone is synthesized form

Answer 5

progesterone and dehydroepiandrosterone

Question 6

Majority of testosterone produced in…

Answer 6

testes = 95%
Adrenal gland <5%

65% bound with SHBG (Sex hormone Binding globulin) in plasma

Question 7

Testosterone converted to dihydrotestosterone by…

Answer 7

5a-reductase

both Test and Dihydrotest affect gene transcription

Question 8

Test effects before birth

Answer 8

masculinizes the repro tract and external genitalia

promotes descent of testes into scrotum

Question 9

Test effects upon sex-specific tissue

Answer 9

Promotes growth and maturation of repro system at puberty

Spermatogenesis

Maintains the repro tract throughout adulthood

Question 10

Test effects other reproductive effects

Answer 10

sex drive at puberty

controls gonads

Question 11

Test effects non-reproductive effects

Answer 11

protein anabolic effect

bone growth at puberty

closes epiphyseal plate

aggressive behavior

causes masculinization of a female

Question 12

Test clinical uses

Answer 12

replace therapy in hypogonadism

stimulate RBC production

suppression of estrogen secretion in women

estrogen suppression with severe endometriosis

treatment of mammary carcinoma in women

illicit use by athletes to increase muscle mass and strenght

Question 13

Androgenic/Anabolic effect ratios

Answer 13

Testosterone 1:1
Testosterone cypionate 1:1
Methyltestosterone 1:1
Fluoxymesterone 1:2
Oxandrolone (Oxandrin) 1:3 – 1:13

Question 14

Test toxicity

Answer 14

largely result of masculinizing effects

Hepatotoxicity
Jaundice
Liver enzymes abnormalities
Hepatocellular carcinoma (rarely)
Priapism or impotence
Increased risk of coronary heart disease in both sexes
Dependence and withdrawal syndrome were reported
Illicit use by athletes – unpredictable rage and hostility

Question 15

Antiandrogens are an important therapy for…

Answer 15

benign and malignant prostate disease. Drugs act at different sites in androgen pathway

Question 16

Ketoconazole

Answer 16

An antifungal agent.

** Inhibits steroid synthesis **

Characterized by antiandrogen and anti-glucocorticoid effects.

Used to treat prostate cancer and Cushing’s syndrome.

Suppresses adrenal steroid synthesis in patients with steroid-dependent metastatic tumors.

Men treated with the drug develop reversible gynecomastia.

Question 17

Finasteride (Proscar and Propecia)

Answer 17

inhibit 5a reductase

useful in benign prostate hyperplasia in reducing prostate size

in women may treat male-type baldness, hirsutism and possibly acne

Question 18

Test Receptor Inhibitors

Answer 18

Cyproterone (Generic)
Flutamide (Eulexin)
Bicalutamide (Casodex)

Question 19

Cyproterone (Generic)

Answer 19

Partial agonist at androgen receptors
Progesterone derivative

Also, affects hypothalamus and decreases GnRH synthesis

Therapy of precocious puberty in males
Masculinization and acne in women
Was proposed to use in treatment of severe hypersexuality in males

Question 20

Spironolactone (Aldactone, CaroSpir)

Answer 20

A competitive inhibitor of aldosterone

** Also competes with dihydrotestosterone for androgenic receptors ***

Therapy of precocious puberty in boys and girls.
Used to treat hirsutism in women.

Question 21

Progesterone

Answer 21

Inhibits GnRH secretion without effect on peripheral tissues

GnRH controls LH and FSH

All exogenous androgens, estrogens and progesterone inhibit GnRH