Repro Owen; Androgens; Kek

Front 1

what hormone do the leydig cells of the testes make?

Back 1

the androgen testosterone is made in the testes

Front 2

where is testosterone produced?

Back 2

leydig cells of the testes, adrenal glands, and small amount in the ovary

Front 3

what are the physiological effects of androgens?

Back 3

1)ANABOLIC: increase in overall body growth, muscle mass, and RBC production; 2)ANDROGENIC: growth of the larynx and skeleton, development of facial hair, darkening of skin 3)virilization and spermatogenic

Front 4

what do androgens stimulate in both sexes?

Back 4

body hair growth, positive nitrogen balance, bone growhth, muscle development, and erythropoiesis

Front 5

explain the serum testosterone levels of a male throughout life.

Back 5

TESTOSTERONE PEAKS: during gestation -fetal male development, at birth, during infancy, then largest peak at puberty; LOW TESTOSTERONE: childhood; testosterone decreases after adulthood as males age

Front 6

what are the serum differences of testosterone levels of men and women while going through puberty?

Back 6

men: ~500ng/dl; women: ~30ng/ml

Front 7

describe the pathway from cholesterol to testosterone synthesis.

Back 7

cholesterol -> pregnenolone -> progesterone -> 17-Hydroxyprogesterone -> Androstenedione -> testosterone

Front 8

if testosterone is in the presence of (CYP 19)aromatase, what does it turn into?

Back 8

Estradiol

Front 9

if testosterone is in the presence of 5 alpha reductase, what does it turn into? where are the intranuclear receptors for this hormone?

Back 9

DHT (dihydrotestosterone) binds better to androgen receptor than testosterone; external genitalia and hair follicles

Front 10

what are the direct effects of testosterone and where are the receptors?

Back 10

receptors are on the internal genitalia for wolffian development during gestation; on skeletal muscle

Front 11

LH acts on ________ cells to produce testosterone and FSH acts on __________ cells to produce inhibin (negative feedback on pituitary).

Back 11

leydig; sertoli

Front 12

How are the synthetic analogues administered and why?

Back 12

because of signigican first-pass metabolism, adrogens are best injected or given transdermally.

Front 13

name some therapeutic uses of androgens.

Back 13

ANDROGENIC EFFECTS: replacement therapy in male hypogonadism; ANABOLIC EFFECTS: (remember anabolism is to build) treat osteoporosis and severe burns, speed recovery from surgery and to counter the catabolic effects of externally administered adrenal cortical hormones; GROWTH promotion in prepubertal body with pituiatry dwarfism; DANAZOL (mild androgen used to treat endometriosis and fibrocystic dz of the breast - no effect on aromatase; AEs: weight gain, acne, decreased breast size, deepening voice, increase libido and hair growth; occasionally reported that it suppresses adrenal function)

Front 14

why are androgens abused? name the precursor to testosterone that is commonly found in these products.

Back 14

athletes and body builders take advantage of androgens anabolic mechanism of building lean body mass, muscle strength, and increase in aggression; DHEA

Front 15

what are the adverse effects of androgen use in females and males?

Back 15

females: virilization, hirsuitism, deepened voice, menstrual irregularities, (if pregnant, virilization of the fetus); MALES: excessive doses can cause feminization because continuous stimulation will inhibit feedback and cause conversion of exogenous androgens to estrogens (gynecomastia, small testes, and infertility); HIGH DOSES also cause behavior effects, including hostility and aggression. BOTH SEXES: cholestatic jaundice, elevate liver enzymes, possible hepatocellular carcinoma

Front 16

list the synthetic androgens.

Back 16

methyltestosterone, fluoxymesterone, oxandrolone, stanozolol

Front 17

there are four categories of androgen antagonists, what are they?

Back 17

1) gonadotropin releasing analogues (leuprolide) given in continuous dose; 2)Receptor Inhibitors (flutamide and bucalutamide and cyproterone); 3) Steroid synthesis inhibitors(ketoconazole and spironolactone); 4) 5alpha reductase inhibitors (finasteride)

Front 18

name the treatments for hypogonadism.

Back 18

androgen replacement therapy includes: testosterone enanthate or testosterone cypionate, methyltestosterone, fluoxymesterone, testosterone patch

Front 19

what meds would you use to treat anabolic protein synthesis?

Back 19

oxandrolone or stanozolol

Front 20

what meds would you use to treat BPH (benign prostatic hypertrophy)?

Back 20

5a reductase inhibitor: finasteride (aka Propecia- used for hairloss)

Front 21

what meds would you use to treat prostate carcinoma?

Back 21

GnRH agonist like leuprolide (continuous dose) given with an androgen receptor antagonist (ie. flutamide); the flutamide is given to prevent the initial surge in testosterone production that may cause a flare in tumor growth

Front 22

what meds would you use to treat hirsutism (hair growth)?

Back 22

combined oral contraceptive, spironolactone (steroid synthesis inhibitor and a K+ sparing diuretic), flutamide (receptor inhibitor), GnRH agonist (continuous dose)

Front 23

in regard to flutamide and bicalutamide, how do they work? when are they used? what are the side-effects?

Back 23

they are nonsteroidal drugs that act as competitive antagonists at teh androgen receptor; used to treat PROSTATE CA (usually in combo with GnRH analogue); S/E: hepatitis and gynecomastia

Front 24

what tissues rely on DHT and therefore would benefit from a 5a reductase inhibitor?

Back 24

prostate and hair follicles have receptors for DHT and since 5a reductase is needed to convert testosterone to DHT, this group of drugs would be benefical in treating BPH and hair loss; since it doesn't affect testosterone action, there are less s/e like impotence, infertility, and loss of libido (FINASTERIDE is the drug)

Front 25

why would combined hormonal contraceptives work in women with hirsutism?

Back 25

since estrogen causes an increase in the SHBG production from the liver, less testosterone would be present in the blood since it would now bind to the SHBG and decrease the androgen effects

Front 26

how does the antifungal, ketoconazole prevent steroid synthesis?

Back 26

ketoconazole reduces the enzyme 17a-reductase; this enzyme is needed to convert many of the steroids into their next steps (ie. from pregnenolone to 17-hydroxypregnenolone); therefore it is used to treat patients with steroid-responsive metastatic tumors

Front 27

what happens when you expose too much hormone to anything?

Back 27

the receptors will downregulate - the mechanism behind contiuous GnRH stimulation