ED

Question 1

4 areas of the brain important in ED? What does each do?

Answer 1

Medial Preoptic Area (MPOA): ability to recognize a sexual partnet
Paraventricular Nucleus (PVN): facilitates penile erection
Paragigantocellular Nucleus (PGN): inhibits penile erection
Locus Coeruleus: integreation (and norepi eignaling)

Question 2

What important hormone is released during sexual stimulation?

Answer 2

Nitrous Oxide (NO)

Question 3

MoA of Nitrous Oxide?

Answer 3

stimulates guanylate cyclase in smooth muscle–> increases cGMP–>relaxes cells (by DECREASING intracellular calcium)–> maintains vasodilation

Question 4

MoA of PDE5 inhibitors? Drug suffix?

Answer 4

Breakdown of cGMP

-afil

Question 5

What do you pay extra attention to in patients presenting with ED? Why?

Answer 5

Risk of CAD! ED often precedes CAD by ~5 years. This is because penile arteries are smallest in the body.

Question 6

Organic vs Psychogenic ED?

Answer 6

Organic: gradual onset, risk factors present, consistent dysfunction incl w/masturbation, no sleep erection.

Psychogenic: opposite

Question 7

In addition to the cGMP system, how else can ED be treated? What drugs do this?

Answer 7

cAMP system can also achieve smooth muscle relaxation via cAMP and PKA. Results in DECREASED intracellular calcium.

Drugs: Prostaglandins

Question 8

What is the most common etiology of ED?

Answer 8

Blood flow issues ~80%

Question 9

Mechanism by which blood flow issues cause ED?

Answer 9

Vascular causes like HPN, obesity, diabetes lead to oxidative stress = endothelial cell injury.