1. Beyond the Condom
Male Contraception

3. Future of male contraception
scenarios:
male pill
male injection
vas deferens block
vas deferens cut
calcium blockers

4. interference with sperm formation
interference with maturation of sperm
interference with energy use of sperm (tail)
interference with ejaculation

6. Sperm production
1) hypothalamus ---> Gnrh
Gnrh--> pituitary
pituitary--> LH and FSH
LH --> stimulates testicles to make testosterone
FSH makes sperm if T helps it along.

7. Can we disrupt sperm?
1) block gnrh ( at Hypothalamus)
2) block LH/FSH
3) interfere with sperm production in teste
interfere with maturation of sperm
vasectomy or block (plug)

8. A problem
If pituitary gland is involved
then
no FSH ( no sperm)
no LH ( no testosterone) Oh! Oh!!!!!!!!!

9. let’s try heat

10. blocking hormones ( gnrh, or lh/fsh) means side
effects ...............no Testosterone

11. other issues
self injection
self medication (pills)
lag time till return to fertility

15. Can we change ( ruin) sperm entry to the egg?

18. we can alter the chemistry of the head (acrosome)
we can change tail function

19. we can:
bind a chemical to the sperm head( blocks egg entry)
disrupt sperm surface protection( sperm death)
block calcium ions crossing plasma membrane( entry)
cholesterol interference on plasma membrane(entry)

20. vas deferens blockade
similar to vasectomy

21. 2 overall routes
1) sperm alteration
2) hormonal alteration

22. up till now
condoms
abstinence
withdrawal
vasectomy
take your trouble in hand

23. contraception
safe?
long lasting
reversible
no side effects
prevents STIs
cheap

24. 10s of millions of sperm mature in
epididymis
cycle is 75 days--> a long process
contraception in testes takes 2 1/2 months
there are always some extra sperm maturing in the
seminiferous tubules

25. stem cells ( spermatogonia) --> divide into
primary spermatocytes = 46 chromosomes ( mitosis)
division to 23 chromosomes ( 2 of them) ( meiosis)
these secondary spermatocytes become spermatids
then spermatazoa
23 chromosome sperm meets 23 chromosome egg

26. Embryo

27. Sex

30. review

31. alter vas deferens patency
alter hormones ( FSH) or Gnrh ( depoprovera )
calcium channel blockers alter lipids in sperm
ejaculation blockers ( separate orgasm from
ejaculation)
render a sperm protein inactive --> sterility (GBAZ protein)
shut down energy use in tail mitochondria protein( SFEC
protein)sperm flagellar energy