Wk3 Male Repro Phys

Question 1

Duration of a full cycle of spermatogenesis; “spermatogenic wave”:

Answer 1

64 days

Question 2

Inhibin inhibits?

Answer 2

anterior pituitary

FSH and LH

Question 3

Testosterone inhibits:

Answer 3

Hypothalamus AND Anterior pituitary

FSH/LH and GnRH

Question 4

LH acts on _______ cells.

Answer 4

Leydig

Question 5

FSH acts on _______ cells.

Answer 5

Sertoli

Question 6

Inhibin comes from _________ cells.

Answer 6

Sertoli

Question 7

Numerical relationship between sperm production and Sertoli cell number:

Answer 7

linear

Question 8

Numerical relationship between sperm production and Leydig cell number:

Why?

Answer 8

Linear

Testosterone helps stimulate Sertoli cells

Question 9

What would decreased testosterone levels do to GrRH?

Answer 9

increase

**less negative feedback

Question 10

Physical musculoskeletal effects of low testosterone:

Answer 10

increased abdominal fat

decreased muscle mass

Question 11

Finasteride

Answer 11

5-a-reductase inhibitor

Tx for: baldness, prostate CA

Question 12

What does 5-a-reductase do?

Answer 12

converts testosterone to DHT (more potent form)

Question 13

Testosterone targets:

Answer 13

Muscle

Seminal Vesicle

Epidydimis

Bone

Question 14

8 mg of daily testosterone in males produced in which two places?

Answer 14

Leydig cells (Testes) — 95%

adrenals — 5%

Question 15

Androgen receptor location and site of action:

Answer 15

cytoplasm — binding of androgens

nuclear transcription factors

Question 16

Anabolic effects of androgens (3):

Answer 16

1. muscle building
2. bone growth – closure of epiphysis
3. Na/H2O retention

Question 17

Read slide….

Answer 17

20

Question 18

Testosterone analog

hormone replacement

hepatotoxic

Answer 18

Methyl testosterone

Question 19

DHT derivative

anabolic steroid

Answer 19

Oxandrolone

Question 20

What happens to gonads with exogenous testosterone use:

Answer 20

shrink

**inhibits hypothalamic pituitary axis –> no stimulation of androgen receptors

Question 21

Read slide…

Answer 21

28

Question 22

Non-steroidal

Pure steroid receptor antagonists

Answer 22

Flutamide

Bicalutamide

Question 23

Difference between “pulsatile” and “continuous” exposure to GnRH analogs:

Answer 23

“pulsatile” is stimulatory

“continuous” is inhibitory

Question 24

GnRH analog (recombinant human form)

pulsatile for 3-6 mo for male infertility

Answer 24

Gonadorelin

Question 25

GnRH analog (synthetic)

continuous for chemical castration in prostate CA

Answer 25

Leuprolide

**initial surge in Testosterone due to hypersecretion of LH and FSH

followed by suppression (~10 days after) due to desensitization of GnRH receptors

Question 26

GnRH recepto blocker

prostate CA

BPH

Answer 26

Degarelix

Question 27

GnRH receptor blocker

blocks premature LH surge in females

Answer 27

Ganirelix

Cetrorelix

Question 28

Major difference between GnRH agonists and antagonists

Answer 28

antagonists don’t have initial hypersecretory phase

Question 29

5-a-reductase inhibitor

BPH

prostate CA

baldness

Answer 29

Finasteride

Question 30

NT for parasympathetic nerve responsible for erection

Answer 30

NO

Question 31

NO second messenger?

Answer 31

Guanalyl cyclase –> increases intracellular cGMP

cGMP promotes arteriole dilation

Question 32

What degrades cGMP in vascular SM to end an erection?

Answer 32

Phosphodiesterase 5

Question 33

Phosphodiesterase 5 inhibitor to facilitate erection:

Answer 33

Sildenafil — Viagra

Tadalafil — cialis — longer duration

Question 34

What not to use with PDE-5 blockers?

Answer 34

alpha-blocker!!!

double whammy on vasodilation –> hypotension