Micturation

Question 1

About how long is the ureter

Answer 1

25-35 cm long

Question 2

How does the ureter help move urine

Answer 2

Undergoes peristalsis like intestines

Question 3

What enhances ureteral peristalsis

Answer 3

Parasympathetic; inhibited by sympathetic

Question 4

What modulates ureteral peristalsis

Answer 4

Sensory nerves

Question 5

What does blocking of ureteral flow cause

Answer 5

Ureteral dilation

Question 6

What often precedes acute renal failure

Answer 6

Hydronephrosis - dilation of the renal pelvis and calyces

Question 7

What is the ureterorenal reflex

Answer 7

Blocked ureter leads to decreased urine output

Question 8

What is the first location of ureteral constriction

Answer 8

UPJ (ureteropelvic junction)

Question 9

What are the 2-4 constrictions of the ureter

Answer 9

• behind testicular or ovarian A or V
• pelvic brim (over external iliac A and V)
• where the ureter transverses the bladder wall

Question 10

What is the the vesicoureteral reflux

Answer 10

Backflow of urine into the ureter and increases the risk of pyelonephritis

Question 11

What is the detrusor muscle

Answer 11

SM of the bladder that contracts in micturition

Question 12

What is the trigone

Answer 12

Posterior wall of bladder where ureters enter bladder and where the bladder neck opens into the posterior urethra

Question 13

What is the internal sphincter of the bladder

Answer 13

SM in the bladder neck that contracts during rest

Involuntary

Question 14

What is the external sphincter of the bladder

Answer 14

Skeletal muscle located in the urogenital diaphragm

Voluntary

Question 15

What does the sensory nerve fibers of the bladder run with

Answer 15

Pelvic splanchnic N or hypogastric plexus

Question 16

Where is the sacral micturition center

Answer 16

S2-4

Question 17

What signals bladder fullness

Answer 17

Aδ fibers

These are myelinated

Question 18

What signals bladder pain

Answer 18

C fibers

These are unmyelinated

More likely in disease states

Question 19

When do parasympathetics predominate in the bladder

Answer 19

When emptying

Question 20

What is the parasympathetic n for the bladder? What does it cause?

Answer 20

Pelvis splanchnic N

Causes detrusor contraction and internal sphincter relaxation

Question 21

What are the receptors of the pelvic splanchnic n

Answer 21

ACh, muscarinic M3

This is the parasymp to the baldder

Question 22

When does the sympathetic response dominate the bladder

Answer 22

Filling

Question 23

What level is the sympathetic of the bladder

Answer 23

L2

Question 24

What is the main sympathetic n for the bladder

Answer 24

Hypogastric n

Question 25

What is the receptor of the hypogastric N

Answer 25

NE

Adrenergic

α1 in the urethra and bladder neck

β2-3 in detrusor muscle

Question 26

What is the somatic nerve for the bladder? What level is it at

Answer 26

Pudendal N

S2-4

Question 27

What does the pudendal n do for the bladder

Answer 27

Urine retention when activated

Question 28

What is the NT and receptor of the pudendal N

Answer 28

ACh and nicotinic

Question 29

Where is the urine storage or “guarding reflex” organized

Answer 29

Spinal cord

Question 30

Where are the voiding reflexes organized

Answer 30

Brain

Question 31

What is responsible for controlling the sacral micturition center

Answer 31

Pontine micturition center or Barringtons nucleus

Question 32

Where does the PMC receive input from

Answer 32

PAG preaqueductal gray

Question 33

What receives afferent bladder signals and passes them on to other brain centers? At what level

Answer 33

PAG

Conscious level

Question 34

What is the primary excitatory input to the PMC

Answer 34

PAG

Question 35

Urination in adults, infant, and parapalegics

Start/Stop
Detrusor and sphincter

Answer 35

Adults: voluntary and in coordination

Infants: involuntary and in coordination

Parapalegic: involuntary and uncoordinated

Question 36

What does activation of the hypogastric N cause

Answer 36

Detrusor m relaxation and internal sphincter contraction