LT2: Therapy of erectile dysfunction

Question 1

What is site of actions of apomorphine (Group 1)?

Answer 1

1) central initiator, main site of action in CNS.

Question 2

What are actions of apomorphine (Group1)?

Answer 2

1) Activate neural signaling pathways leading to initiation of penile erection.
2) Action orally (in special buccal form), it can be given orally.
3) Stimulates erection in both normal men & those w ED.

Question 3

What are actions of alprostadil (Group2), IV drug?

Answer 3

1) Action in periphery to activate events (peripheral initiator), leading to penile erection.
2) Binds prostaglandin E1 receptor, leading to cAMP- mediated smooth muscle relaxation.

Question 4

What is the action of group 3 & 4 drugs for ED?

Answer 4

Group 3: central conditioner.
Group 4: peripheral conditioner.

Both of them improve local or systemic internal millieu of CNS, which enhances or enables penile erection.

Question 5

What is the action of trazodone (Group 3)?

Answer 5

1) They do not in their own initiate the erection.

2) Selective serotonin reuptake inhibitor.

Question 6

What are the actions of Sildenafil (Group 4)?

Answer 6

1) Selective inhibitor of cGMP- specific phosphodiestrase-5 & inhibition of the degradation of cGMP, leading to release of NO & smooth muscle relaxation.
2) Enhances erction by augementing NO-mediated reaction.
3) Orally effective & well-tolerated.

Question 7

What are the actions of Papaverine (Group 4)?

Answer 7

1) Non-specific phosphodiestrase inhibitor, leading to high cAMP & cGMP in penile erectile tissue.
2) Smooth muscle relaxant & vasodilator.
3) Highly effective in men w/ psychogenic/ neurogenic ED.

Question 8

What are actions of Phentolamine (Group 4)?

Answer 8

1- Non-selective a-adrenoreceptor blocker.
2- Orally & IV.
3- T (0.5) is 30 min & duration of action 2-4 hrs.