T3 L11: Lower urinary tract

Question 1

Where does tubular fluid exit the collecting ducts?

Answer 1

At the tip of the renal pyramid (the renal papilla)

Question 2

What is the site of drug-induced nephrotoxicity?

Answer 2

The renal papilla (renal papillary necrosis)

Question 3

Which structures fuse to form the renal pelvis?

Answer 3

Major calices

Question 4

What triggers peristaltic contraction in the kidneys?

Answer 4

The fluid moving into the renal pelvis and causing distention

Question 5

What are the 2 types of muscle that make up the ereters?

Answer 5

Inner muscle is longitudinal and outer muscle is circular

Question 6

How many peristaltic waves are generated per minute in the ureters?

Answer 6

1-6 per minute

Question 7

What type of epithelium makes up the mucosal layer of ureters?

Answer 7

Transitional epithelium

Question 8

What is the effect of the parasympathetic NS on the number of peristaltic contraction in ureters?

Answer 8

Enhance

Question 9

What is the effect of the sympathetic NS on the number of peristaltic contraction in ureters?

Answer 9

inhibition

Question 10

Describe the process of peristalsis in ureters

Answer 10

1. longitudinal muscle contracts and circular muscles relaxes
2. Longitudinal muscle relaxes so a bolus forms and then circular muscle contracts to push the bolus

Question 11

Which structures prevent backflow of urine in the bladder?

Answer 11

The ureteral openings

Question 12

What is the detrusor muscle layer in the bladder?

Answer 12

The outer muscle layer consisting of longitudinal muscle and circular muscle

Question 13

What is the trigone and what is its function?

Answer 13

A triangular area bound by openings of the ureters and entrance to the urethra. It acts as a funnel to channel urine towards the neck of the bladder

Question 14

Which NS stimulates the bladder to contract?

Answer 14

The parasympathetic NS

Question 15

What are the 2 urethral sphincters?

Answer 15

Internal and external

Question 16

Which urethral sphincter is under involuntary control?

Answer 16

The internal sphincter

Question 17

Why does incontinence after childbirth occur in women?

Answer 17

Because the female external sphincter is not as well developed

Question 18

What is mucturation?

Answer 18

Urination

Question 19

What impact do higher centres have on micturation?

Answer 19

They keep the micturition reflex under inhibition

Question 20

What impact do cortical centres have on micturition?

Answer 20

They facilitate micturition by initiating the micturating reflex and relaxing the external sphincter. The internal sphincter relaxes at the same time

Question 21

What happens to contractions when the bladder becomes increasingly full?

Answer 21

Contractions become more frequent, intense, and last longer

Question 22

Which nerve carries sympathetic involuntary control to the bladder and sphincters and from which vertebral level?

Answer 22

The hypogastric from L2

Question 23

Which nerve carries parasympathetic involuntary control to the bladder and sphincters and from which vertebral level?

Answer 23

The pelvic nerve from S2 and S3

Question 24

Which nerve carries somatic voluntary control to the bladder and sphincters and from which vertebral level?

Answer 24

The pudendal nerve from S2 and S3

Question 25

Which nerves inhibit micturation?

Answer 25

The hypogastric and pudendal nerve

Question 26

Which nerve facilitates micturation?

Answer 26

The pelvic nerve

Question 27

What stimulates the pelvic nerve?

Answer 27

Activation of stretch receptors in the bladder wall and internal sphincter

Question 28

Describe the guarding reflex

Answer 28

Bladder distention stimulates the pelvic nerve which stimulates the hypogastric nerve. Stimulation of the hypogastric nerve causes relaxation and reduced excitability of the detrusor muscle and constriction of the internal sphincter. The external sphincter is held closed by the pudendal nerve

Question 29

After how many mL are micturition contractions stimulated?

Answer 29

200 mL

Question 30

Which muscles are involved in micturition?

Answer 30

Lowering of the diaphragm, contraction of abdominal muscles, and opening of the internal sphincter

Question 31

What is Paraplegia?

Answer 31

The complete severing of nerve input from the cerebral cortex. It means there is no cortical control

Question 32

What causes an automatic bladder?

Answer 32

Paraplegia

Question 33

What is meant by an automatic bladder?

Answer 33

The involuntary emptying of the bladder

Question 34

What causes an unintended bladder?

Answer 34

Partial spinal cord damage with loss of inhibitory descending signals

Question 35

What is an unintended bladder?

Answer 35

Frequent urination as excitatory impulses from cerebral cortex remain unopposed

Question 36

What causes an atonic bladder?

Answer 36

Crush injury of the dorsal root causing afferent nerve destruction so micturition reflexes are lost

Question 37

What is an atonic bladder?

Answer 37

When the bladder fills till it overflows

Question 38

Why do infants lack the voluntary mechanism to control urination?

Answer 38

Their corticospinal connections are not established

Question 39

Which diseases can cause loss of micturition control?

Answer 39

Stroke, Alzheimer's, problems affecting cerebral cortex

Question 40

What cause cause bladder sphincter muscles to lose tone?

Answer 40

Pregnancy

Question 41

What diseases can cause urinary retention?

Answer 41

Enlarged prostate gland because it compresses the urethra

Question 42

What foods can cause heightened urge incontenence?

Answer 42

Spicy food (capsaicin), caffeine/chocolate (xanthine's), citrus food (citric acid), and carbonated beverages

Question 43

What does ACh released by the pelvic nerve cause?

Answer 43

Promotes micturition

Question 44

What di anticholinergic drugs do?

Answer 44

Inhibit bladder contractions and facilitate involuntary contractions of the internal sphincter

Question 45

Oxybutinin is a type of which drug?

Answer 45

An anticholinergic drug

Question 46

What are some unwanted effects of anticholinergic drugs?

Answer 46

Dry mouth, blurred vision, palpitations, drowsiness, facial flushing

Question 47

What is atropine?

Answer 47

1. Increases the heart rate and improves the atrioventricular conduction by blocking the parasympathetic influences on the heart 2. It dilates vessels

Question 48

What type of drug is Imipramine?

Answer 48

A tricyclic antidepressant

Question 49

When is Imipramine used?

Answer 49

Low doses are given to children who wet the bed. It can cause behavioural problems on withdrawal

Question 50

What type of drug is Desmopressin and what is it used for?

Answer 50

It's and ADH analogue used for children who wet the bed

Question 51

What type of drug is Mirabegron and what is it used for?

Answer 51

A selective beta-2 agonist used for overactive bladder syndrome

Question 52

What is the treatment for acute urinary retention?

Answer 52

Catherisation or surgery

Question 53

What is the treatment for chronic urinary retention?

Answer 53

Pharmacological intervention or surgery

Question 54

What does noradrenaline released by the hypogastric nerve do?

Answer 54

Reduces micturition

Question 55

What type of receptors are found on the prostate and external sphincter?

Answer 55

Alpha-1 receptors

Question 56

What are alpha-1 receptors stimulated by?

Answer 56

noradrenaline

Question 57

What do stimulated alpha-1 receptors do to urinary flow?

Answer 57

Increase it

Question 58

Alfuzosin, Doxazosin, Indoramin, Prazosin, Tamulosin, and Terazosin are types of which drug?

Answer 58

Alpha-1 agonists

Question 59

What do parasympathomimetics (choline esters) do?

Answer 59

They have agonist action at muscurinic ACh receptors that cause increased contractions of the detrusor muscle

Question 60

What are parasympathomimetics (choline esters) used for?

Answer 60

To treat urinary retention

Question 61

What type of drug is Bethanecol?

Answer 61

A parasympathomimetic (choline ester)

Question 62

What are the unwanted effects of parasympathomimetics (choline esters)?

Answer 62

Nausea, vomiting, intestinal colic, bradychardia, blurred vision, sweating

Question 63

What do Neostigmine and Pyridostigmine do?

Answer 63

They inhibit the breakdown of ACh and promote bladder emptying (Incontinence)

Question 64

What are Pinasteride and Dutasteride and what are they used for?

Answer 64

They're inhibitors of androgen synthesis used to relieve urinary retention caused by prostate hyperplasia