Flashcards in Erectile Dysfunction Deck (16):
Which muscles contract to increase vascular pressure in the penis?
Bulbocavernosus and ischocavernosus muscles
Innervated by pudendal nerve (somatic).
Spinal cord levels for sympathetics
Spinal cord levels for parasympathetics
S2,3,4 keep the penis off the floor
Which nerve does the dorsal nerve of the penis join?
Which SC levels does this nerve enter?
Joins pudendal nerve, which enters S2-4 spinal roots (Onuf's nucleus)
Center of somatomotor penile innervation in S2-4 spinal cord
Messenger molecules for erection
•NO is the primary messenger. cGMP / cAMP are the secondary messengers.
•NO → guanylyl cyclase → conversion of GTP to cGMP → decrease in Ca → relaxation allowing for increased blood flow.
Characteristics of psychogenic ED
•Nocturnal erections are maintained
•Mechanism – inhibition of spinal erection center as exaggeration of normal suprasacral inhibition and sympathetic outflow. May also involve elevated catecholamines preventing relaxation of penile smooth muscle.
Testosterone threshold for erections
At what testosterone level should you suspect hyperprolactinemia?
Less than 150 ng/dL
Effects of hyper / hypothyroidism on sexual function
•Hyperthyroidism decreases libido. •Hypothyroidism → low testosterone secretion and elevated prolactin.
Risk factors for arteriogenic ED (6)
Same risk factors as heart disease: HTN, hyperlipidemia, smoking, DM, trauma, irradiation.
Treating venogenic ED
What does not work?
Treat w/ therapies to increase flow (PDE5 inhibitors, injection) or decrease outflow (constriction bands).
Surgery to occlude veins does not work.
Substance abuse causing ED (3)
Cigarettes, alcohol, marijuana
Meds causing ED (8)
•Anti-hypertensive: Thiazides, B-blockers
•CNS: Sedatives, anti-depressants, analgesics
•Histamine receptor blockers
•Long-lasting LHRH-agonists, estrogen
Lifestyle changes to treat ED (5)
•Reduce fat / cholesterol in diet, decrease alcohol, eliminate tobacco / substance abuse, weight loss, regular exercise