Urogenital

Question 1

3 important parts of bladder

Answer 1

detrusor muscle (contracts - urine out). trigone (contracts = retention). sphincter.

Question 2

autonomic outflow coordinates? normally what type of activity?

Answer 2

bladder detrusor smooth muscle + outlet (bladder neck, urethra, sphincter). reciprocal activity.

Question 3

urine storage: bladder is? pressure?

Answer 3

bladder is quiescent. intravesical pressure constant, despite large increases in urine volume.

Question 4

how is continence maintained during bladder filling?

Answer 4

autonomic drive to smooth muscle controlling outlet increases during bladder filling

Question 5

during micturition, what contracts/relaxes?

Answer 5

bladder contracts, outlet relaxes

Question 6

bladder voiding mediated by ___ reflex? mediated by?

Answer 6

spinobulbal reflex. pontine micturition centre aka PMC.

Question 7

PMC regulated by? “switch”?

Answer 7

regulated by higher centers to determine time/place of micturition. “switch” from storage to elimination mode = afferent fibers from bladder via pelvic nerve that signal filling

Question 8

sacral parasympathetic outflow: via what nerve? type of input? promotes?

Answer 8

via pelvic nerve, major excitatory input = promotes voiding.

Question 9

sympathetic ouflow: from where? via what nerve? main effect?

Answer 9

thoracic level of SC, via hypogastric nerve. urinary continence.

Question 10

3 effects of sympathetic ouflow

Answer 10

inhibit bladder detrusor smooth muscle. excite bladder base/urethra (where sphincters are). modulate transmission in parasympathetic ganglia.

Question 11

volutnary/somatic outflow to where? via what nerve?

Answer 11

to skeletal muscle of external sphincter. pudental nerve.

Question 12

in infants, bladder function is ______? which means?

Answer 12

neurogenic: depends directly on spinal reflexes

Question 13

key to understanding bladder reflexes:

Answer 13

weak afferent activity has a different effect from strong afferent activity (weak = retention, strong = voiding)

Question 14

urine storage reflex: what in the afferent pathway?

Answer 14

low level of vesical afferent activity in pelvic nerve

Question 15

urine storage reflex: what in the efferent pathway? (5)

Answer 15

somatic nerves to contract external sphincters. sympathetic nerves contract internal sphincter, inhibit detrusor, inhibit parasympathetic ganglia. sacral ganglionic parasymp ouflow is inactive

Question 16

sympathetic modulation of parasympathetic ganglia?

Answer 16

release NA onto parasympathetic terminals = presynaptic inhibition on a2 recetpors, inhibit ACh release from parasympathetic nerves

Question 17

micturition reflex: what in the afferent pathway?

Answer 17

high level of vesical afferent activity, pelvic nerve

Question 18

micturition reflex: what in the efferent pathway? (3)

Answer 18

somatic nerve: inhibit external sphincter. inhibit sympathetic ouflow. activate parasymp. outflow

Question 19

sacral parasymp. outflow uses ___ as NT?

Answer 19

uses peptides and ATP, in addition to ACh