ED and BPH Pathophysiology Exam 3

Question 1

function of corpora cavernosa

Answer 1

control the sinusoidal blood capacity

Question 2

function of corpora helicine arteries

Answer 2

supply blood to the sinusoids of the erectile tissue

Question 3

function of corpora subtunical veins

Answer 3

collect blood from the sinusoids

Question 4

function of corpora circumflex veins

Answer 4

collects blood from the subtunical veins

Question 5

function of corpora cavernosal veins

Answer 5

drains the proximal portions of the corpora cavernosa

Question 6

Parasympathetic role in erection

Answer 6

Principal mediators of erection

Question 7

Sympathetic role in erection

Answer 7

Principal mediators of ejaculation and detumsecence

Question 8

Testosterone

Answer 8

• Normal serum concentration is 300 to 1100 ng/dL
• stimulates libido and increases levels of nitric oxide and cGMP
• Free testosterone accounts for 2% of blood levels and is the active form

Question 9

What is the key modulator of erection?

Answer 9

the tone of the smooth muscle walls of the helicine arteries and the trabecular spaces

Question 10

The tone of an erection is controlled by what?

Answer 10

level of intracellular calcium in the smooth muscle cells

Question 11

Which neurotransmitters influence intracellular calcium levels?

Answer 11

• Nitric oxide (NO)
• Vasoactive intestinal polypeptide (VIP)
• Prostaglandin E1 (PGE1)
• Norepinephrine (NorEpi)
• Acetylcholine

Question 12

Acetylcholine

Answer 12

indirectly enhances arterial flow to the corpora

Question 13

Nitric oxide (NO)

Answer 13

• Most important NT for erection
• Released from the endothelium stimulated
• Testosterone enhances the release of nitric oxide
• ACh enhances release of nitric oxide
• Activates guanylate cyclase to convert guanosine triphosphate (GTP) into cyclic guanosine monophosphate (cGMP)

Question 14

phosphodiesterase-5 (PDE5)

Answer 14

brakes down cGMP which ends the erection

Question 15

Vasoactive intestinal polypeptide (VIP)

Answer 15

• Simulates the production of cyclic adenosine monophosphate (cAMP) from adenosine triphosphate (ATP)
• Reduction in intracellular calcium

Question 16

Prostaglandin E1 (PGE1)

Answer 16

• Stimulates the production of cAMP from ATP

- Reduction in intracellular calcium

Question 17

Norepinephrine (NorEpi)

Answer 17

• Released from sympathetic nerves within the corpora cavernosa and activates alpha1receptors on the smooth muscle cells
• increased intracellular calcium which causes contraction / vasoconstriction

Question 18

psychogenic process of erection

Answer 18

• Audiovisual stimuli or fantasy may initiate erection
• also contains tactile stimulation
• Spinal erection center sends messages to cavernosal nerves

Question 19

Parasympathetic Stimulation

Answer 19

• Dilation of the cavernosal and helicine arteries, increasing blood flow into the lacunar sinusoidal spaces
• Relaxation of cavernosal smooth muscle, opening the vascular lacunar spaces
• Expansion of the lacunar spaces which decreasing venous outflow and producing a rigid erection
• called the veno-occlusive mechanism

Question 20

psychogenic ED

Answer 20

• Performance anxiety
• Relationship problems
• Loss of attraction for a partner
• Stress
• Depression

Question 21

organic ED

Answer 21

• Neurogenic
• Hormonal
• Vasculogenic
• Drug-induced
• Other

Question 22

organic ED: neurogenic

Answer 22

• Failure of the body to initiate nerve impulses needed for erection or when there is an interruption of the neural transmission needed to initiate and sustain an erection
• Results from: stroke, Alzheimer’s disease, spinal cord injury, radical pelvic surgery, diabetic neuropathy, pelvic injury, intervertebral disc lesion, multiple sclerosis, serious cyclists, and trauma

Question 23

organic ED: hormonal

Answer 23

• Inadequate hormonal activity for erection

- low testosterone levels, high hormone-binding globulin, high prolactin levels -> hypogonadotropic hypogonadism

Question 24

organic ED: vasculogenic

Answer 24

• damaged blood vessels -> inadequate arterial blood flow to initiate and maintain an erection
• Associated conditions include: atherosclerosis, hypertension, diabetes, trauma, Peyronie’s disease, pelvic irradiation, and hyperlipidemia

Question 25

organic ED: drug induced

Answer 25

- Antihypertensives - Dopamine antagonists - Anticholinergics - Estrogen or antiandrogenic drugs - CNS Depressants - Misc others

Question 26

What is the most common cause of ED?

Answer 26

Most cases are multifactorial in origin

Question 27

What are the 3 hormones that may play a role in prostate enlargement?

Answer 27

- testosterone - 5-alpha dihydrotestosterone - estrogen

Question 28

What is the principal circulating androgen?

Answer 28

testosterone

Question 29

What is estrogen's role in BPH enlargement?

Answer 29

may act synergistically with dihydrotestosterone to induce prostatic growth by enhancing the amount of androgen receptor protein in the stromal tissue

Question 30

symptoms commonly associated with BPH: lower urinary tract symptoms (LUTS)

Answer 30

- Difficulty initiating a urinary stream - Hesitancy (a hesitant, interrupted, weak urine stream) - Incontinence (leaking or dribbling) - Sensation of incomplete emptying of the bladder - Nocturia (more frequent urination at night) - Urgency (a sense of needing to urinate) - Frequency - Urinary tract infections - Bladder or kidney damage - Formation of bladder stones

Question 31

causes of acute urinary retention

Answer 31

- OTC decongestants/alpha agonists (Phenylephrine, Pseudoephedrine) - Antihistamines - Anticholinergics - Tricyclic Antidepressants - Phenothiazines - Excessive use of alcohol - Cold temperature - Long periods of immobility