Week 8 - Neuronal Control Of Bladder

Question 1

Describe pressure changes in the bladder during the storage phase?

Answer 1

Remains constant til a point when jt increases very fast, this is when feel desperate for the toilet

Question 2

Describe the pressure changes in the bladder during the voiding ohase?

Answer 2

Goes in waves gradually downwards caused by contractions of the detruser muscle

Question 3

What receptors are there in the bladder wall? Stretch receptors
Describe the sensory innervation of the storage phase?

Answer 3

Stretch receptors in the bladder wall detect low stretch (this reflex is only active at low levels of stretch)
nerve enters spine at S4 but ascends up to T1@ where it acts on the sympathetic nerve

Question 4

What is the sympathetic innervation of the bladder during storage phase?

Answer 4

nerve leaves at T10 and casues decreased contractions of detrusor muscle (causes bladder to relax as it fills) and acts to increase contraction of smooth muscle of internal urethral sphincter

Question 5

Describe the somatic motor innervation of the bladder during the storage phase?

Answer 5

Travels down from L centre in brain and leaves at S4, acts to increase contraction of skeletal muscle of external urethral sphincter

Question 6

Describe the sensory innervation of the bladder during the voiding phase?

Answer 6

Act to stimulate parasympathetic innervation and stimulate the M centre in the brain

Question 7

Describe the parasympathetic innervation of the bladder during the voiding phase?

Answer 7

Leaves S2-S4 and causes contrations of the detrusor muscle in the bladder wall

Question 8

Describe the somatic motor innervation of the bladder during the voiding phase?

Answer 8

m centre in brain acts on parasympathetic to increase bladder wall contractions, it also acts to inhibit the L centre in the brain causing the external sphincter to relax and inhibits the sympathetic innervation to the bladder causing the internal sphincter to relax, there are also nerves going to and from the cortex stimulating and inhibiting the M centre allowing full bladder control no matter how full it is