Micturation Control

Question 1

Journey of the urine from kidney to bladder (contractions)

Answer 1

Peristaltic waves of contraction brings urine from the pelvis of the kidney to the bladder

Question 2

What occurs when there is a sufficient amount of urine in the bladder

Answer 2

Stretch receptors sense this and cause reflex parasympathetic innervation of the DETRUSOR muscles of the bladder.
This coupled with the relaxation of the external sphincter muscles, allows urine to pass out the urethra and out of the body

Question 3

What accelerates the process of urination?

Answer 3

Abdominal muscles voluntarily cause the forcing of urine out at a faster rate

Question 4

Voluntary control of micturition is caused by

Answer 4

The descending spinal pathways inhibiting parasympathetic output
Additionally stimulating the somatic nerves for the continued contraction of the external urethral sphincter

Question 5

What spinal damage can mean for micturition

Answer 5

Loss of voluntary control of urination
Inability to urinate, ie damage to parasympathetic nerves which supply detrusor muscles. (Ability to empty bladder efficiently is lost

Question 6

Which 2 types of nerves report about bladder stretch?

Answer 6

Parasympathetic nerves
Sympathetic nerves (hypogastric)

Question 7

What muscles are the min contractile muscles in. The bladder?

Answer 7

DETRUSOR muscles

Question 8

What effect does sympathetic nerves have in the DETRUSOR muscles?

Answer 8

Inhibitory

Question 9

What effect does parasympathetic nerves have in the detrusor muscles

Answer 9

Excitatory effect

Question 10

Which nerves are internal urethral sphincter muscles innervated by?

Answer 10

Sympathetic efferent

Noradrenaline release

Question 11

What catecholamine is released by the somatic nerves when innervation the external sphincter muscle?

Answer 11

Acetylcholine

Question 12

What innervates the external sphincter muscles of the urethra

Answer 12

The somatic motor fibres

Question 13

What type of nervous innervation stimulates internal sphincter muscles?

Sympathetic or parasympathetic

Answer 13

Sympathetic (sympathetic efferent)

Question 14

What type of nervous innervation stimulates external sphincter muscles?

Sympathetic or parasympathetic

Answer 14

Parasympathetic

Somatic nerves

Question 15

What neurotransmitter is released by sympathetic nerves

Answer 15

Adrenaline

Noradrenaline

Question 16

What neurotransmitter is released by parasympathetic nerves

Answer 16

Acetylcholine

Question 17

Where do somatic nerves enter the spinal cord

Answer 17

S2 and S4

Question 18

Where do the pelvic or parasympathetic nerves emerge

Answer 18

S2-S4

Question 19

Where do the sympathetic nerves enter

Answer 19

T11-T12

Question 20

What also detects stretch in the bladder

Answer 20

ICCs

Question 21

Causes the micturation reflex

2 things

Answer 21

Bladder stretch leading to bladder contraction

Question 22

What is the interface layer of the bladder?

Answer 22

MUSOCAL LAYER

Question 23

What type of epithelium is in the mucosal layer of the bladder?

Answer 23

Transitional epithelium

Question 24

Which layer of the bladder is sensory?

Answer 24

Submucosa layer

Question 25

What type of layer is the detrusor layer of the bladder?

Answer 25

Contractile

Question 26

What function do PONS have in micturition

Answer 26

Speak to higher brain centres Inhibits parasympathetic efferent Relaxes bladder PREVENTS MICTURITION

Question 27

Effect of full bladder on PONS

Answer 27

Pons stop inhibiting the parasympathetic efferent and allow contraction of detrusor muscles

Question 28

What do pons do in voiding

Answer 28

Stop inhibiting: Parasympathetic efferents to detrusor = detrusor contraction Sympathetic efferent signals stopped= internal sphincter relaxes Somatic efferent signals switched off by PONS= External sphincter relaxes

Question 29

What is an Antonic bladder?

Answer 29

A dilated urinary bladdder that does not empty

Question 30

What types of problems could lead to overflow incontinence | 4 things

Answer 30

BPH (benign prostatic hyperplasia) Sensory nerve damage during child birth Anticholergnergic drugs ↓ parasympathetic Epidurals ↓ sensation

Question 31

Treatments for overflow incontinence (caused by ↓ parasympathetic innervation)

Answer 31

M3 Agonist Catheterisation Remove prostate

Question 32

What is stress incontinence

Answer 32

Voiding of urine upon sneeezing, exercising, coughing

Question 33

How does a weak pelvic floor cause stress incontinence

Answer 33

The external urethral sphincter doesn’t function effectively, leading to voiding on coughing/sneezing/exercise

Question 34

Treatments for stress incontinence (Weakness of pelvic floor muscles and external sphincter)

Answer 34

Pelvic floor exercises, bladder training, ↓ fluid intake, Artificial sphincter (external)

Question 35

What is urge incontinence?

Answer 35

Overactive bladder, frequency and urgency day and night, with or without loss of bladder control

Question 36

What causes overactive bladder? (Urge incontinence)

Answer 36

Oversensitivity due to UTI Overstimulation of detrusor Obesity, constipation, diabetes

Question 37

Treatments for overactive bladder (think ↓ parasympathetic)

Answer 37

Antimuscarinic medications Botulinum toxin (↓ AcH release) Drink more water, bladder training NSAIDs to ↓ inflammation

Question 38

Neurogenic bladder dysfunction caused by

Answer 38

Spinal cord injury Crush injury Severance of ascending or descending inputs

Question 39

What would happen if a patient had a T2 spinal cord injury

Answer 39

Overactive detrusor, due to no inhibitory influences above External urethral sphincter unable to relax Catheterisation needed No voluntary control of micturition

Question 40

How to reduce overactive voiding in neurogenic bladder dysfunction

Answer 40

Muscarinic antagonists Botox or reduce AcH release Desensitisation of ICCs with capsaicin

Question 41

What is the function of capsaicin in neurological bladder dysfunction?

Answer 41

Desensitises the ICCs to stretch in the bladder

Question 42

What does Botox reduce in parasympathetic neurones

Answer 42

Acetylcholine release

Question 43

How are muscarinic antagonists used in treatment of bladder dysfunction/overfunction

Answer 43

Prevents parasympathetic stimulation of the DETRUSOR muscles, ↓ voiding potential