16 17 Male Reproductive Flashcards Preview

Endocrine (updated 2016) > 16 17 Male Reproductive > Flashcards

Flashcards in 16 17 Male Reproductive Deck (32):
1

What happens in the epididymis, ductus deferens, and urethra

system of ducts - Transport and stores sperm assists in their maturation, and conveys them to the exterior

2

What are examples of accessory sex glands

Seminal vesicles, prostate, and bulbourethral glands

3

What is the critical regulator of male reproductive function

androgens and other hormones

ALL functions & differentiation regulated by hormones

4

The first fetal repro structure is female, male, or both

Both

5

What does the Mullarian duct become? How is the process regulated?

Female repro organs - NOT under hormonal control
fallopian tube / oviduct
uterus
cranial 1/3 of vagina

6

What does the Wolfian duct become

Male repro organs - require MIS/AMH stimulation
epididymis
vas deferens
seminal vesicle

7

What do sertoli cells do to the male repro tract

secrete MIS/AMH to induce Mullerian duct regression

8

What do leydig cells do to the male repro tract

secrete testosterone to induce Wolffian duct development

9

What does MIS/AMH do?

Hormone produced by sertoli cells that causes Mullerian duct regression

10

What are the 3 phases of spermatogenesis

Proliferation
meiotic
differentiation

11

What drives spermatogenisis

Leydig cells and the androgens they produce

spermatogenesis is obligatory dependent on androgen

12

What are the two populations of Leydig cells

1) Fetal leydig cells
- differentiate prenatally
- produce androgens that induce normal development of male internal and external reproductive organs
2) Mature leydig
- develop at puberty
- drive spermatogenesis and other events

13

What do the testes do

produce androgen
produces sperm

14

What species have a prostate

present in all species

15

What species do not have seminal vesicles

absent in dogs and cats

16

What species do not have bulbourethal glands

bears, dogs, aquatic animals

17

What is the major producer of semen

seminal vesicles

18

What is cryptorchidism

Testicle doesn't descend properly
0.8-15% of dogs
can be treated surgically & medically
if untreated more prone to tumors

19

What is Benign prostatic hyperplasia

begin NOT cancer
enlargement of the prostate gland
occurs only in dogs and humans

20

What causes BPH symptoms? Treatment?

age and time
clinical symptom in dogs: incontinence

Treatment: castration

21

gonads / testes

produces sperm
secretes hormones

22

What is the function of the male reproductive system

produces androgens & other hormones
produces male gametes
conveys the gametes from their site of production into the female reproductive tract

23

3 cells types in the testis that play critical roles in reproduction

germ cells
- spermatogonia > spermatozoa
sertoli cells
- regulate germ cell development
interstitial (leydig) cells
- secrete testosterone, the major androgen

24

spermatogenesis

development of spermatids into sperm
65-75 days in humans - variable in species
sertoli cells important

25

What drives androgen production by Leydig cells?

hypothalamus releases GnRH into the blood stream →
GnRH triggers the release of pituitary LH and FSH → stimulate the testes to secrete testosterone and produce sperm

26

Hormonal control of the testes

a puberty > increased GnRH from hypothalamus > Anterior Pituitary increases secretion of LH and FSH

LH stimulates leydig cells to secrete testosterone
FSH acts indirectly on spermatogenesis

27

What does lutenizing hormone (LH) regulate in male reproduction

stimulates Leydig cells to secrete testosterone
- testosterone stimulates spermatogenesis
- synthesized from cholesterol in testes
- suppresses secretion of LH and GnRH via negative feedback

28

What does follicle stimulating hormone (FSH) regulate in male reproduction

acts on sertoli cells
- FSH & testosterone act on sertoli cells to promote spermatogenesis and stimulate secretion of androgen binding protein (APB)
- APB binds to testosterone keeping concentration high
- sertoli cells release inhibin which inhibits FSH

29

How does androgen act to support and promote spermatogenesis?

sertoli cells are the ONLY cells in the seminiferous tubules that express androgen receptor

androgens from the leydig cells act on sertoli cells to drive spermatogenesis

androgenic regulation of spermatogenesis is INDIRECT; germ cells do not have androgen receptor and are not responding directly to androgens

30

What are the functions of androgens produced in leydig cells?

- support spermatogenesis
- induce and maintain make accessory sex organs
- influence brain and sexual behavior
- promote protein anabolism, muscle mass, somatic and bone growth
- regulate secretion of gonadotropins
- induce secondary male sex characteristics (horns, mane, feathers, rooster comb, etc. )

31

What are some clinically important male repro diseases and problems in vet med

cryptorchidism
infertility
benign prostatic hyperplasia (BPH)
testicular tumors

32

testicular tumors

can occur in many diff cells in testes:
- sertoli cell tumors
- seminomas
- interstitial cell tumors
ALL can be malignant