PBL 8 Flashcards

1
Q

What is the uretorenal reflex?

A

Prevents excessive flow of urine into the pelvis of a kidney when the ureter is blocked
Pain nerve fibres supplying the ureters detect blockage and cause a sympathetic reflex back to the kidney to constrict renal arterioles, decreasing the renal output from the kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the vesicoureteral reflex?

A

This is where some urine in the bladder is propelled backwards into the ureters
This can lead to enlargement of the ureters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the voiding reflex?

A

This is where once you have started to expel urine from the bladder, sensory signals are sent to the sacral plexus
This further stimulates signals through the pelvic splanchnic nerve to cause contraction of the detrusor muscle until the bladder is empty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How much urine remains in the bladder after micturition?

A

Less than 10mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How can higher centre control prevent micturition?

A

Firing signals through the voluntary pudendal nerve

This causes continual tonic contraction of the external sphincter until a continent time presents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the parasympathetic control of micturition?

A

Pelvic splanchnic nerve arises from S2-S4
Synpases on M3 receptor on bladder and releases ACh
This causes contraction of the detrusor muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the sympathetic control of micturition?

A

Hypogastric nerve arises from T10-L2
Synapses on B3 receptor on bladder and releases noradrenaline - this causes inhibition and relaxation of detrusor
Synapses on alpha 1 receptor on internal sphincter - causes contraction of sphincter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does the bladder know when it is empty or full?

A

The amount of sensory signals coming from the bladder detects the stretch in the bladder wall - the more signals coming, the fuller the bladder is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which part of the brain is responsible for controlling micturition?

A

Pons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 4 types of urinary incontinence?

A

Urge incontinence
Stress incontinence
Overflow incontinence
Functional incontinence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens in urge incontinence?

A

You have an overactive bladder, which results in the sudden urge to urinate

Due to an uninhibited detrusor muscle which contracts randomly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens in stress incontinence?

A

Increased abdominal pressure overwhelms the sphincter muscles allowing urine to leak out

E.g, sneezing, coughing, laughing, during pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens in overflow incontinence?

A

Problem with emptying the bladder due to:

  • blockage (e.g, BPH)
  • ineffective detrusor muscle
  • ineffective signalling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the function of the prostate?

A

Release alkaline fluid in semen to help neutralise acidity of the vagina
Contains smooth muscles that help to expel semen during ejaculation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 4 zones of the prostate and where are they?

A

Central zone - surrounds the ejaculatory ducts
Transitional zone - centrally surrounds the urethra
Peripheral zone - posteriorly (largest zone)
Fibromuscular stroma - anteriorly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which part of the prostate is most likely to undergo BPH?

A

Transitional zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which part of the prostate is most likely to undergo prostate carcinoma?

A

Peripheral zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the function of prostate specific antigen (PSA)?

A

Protease which breaks down the high molecular weight of seminal coagulum into smaller polypeptides

19
Q

What cells produce PSA?

A

Prostatic epithelial cells

20
Q

How does testosterone regulate prostatic growth?

A

Converted into dihydrotestosterone (DHT) in prostatic stromal cells by 5alpha-reductase type 2
DHT binds to nuclear androgen hormone receptors in both stromal and epithelial cells that regulate gene expression of growth factors

21
Q

How much more potent is DHT than testosterone?

A

1000x more potent

22
Q

What important growth factors does DHT cause expression of?

A

Fibroblast growth family (FGF)

23
Q

What does LUTS stand for?

A

Lower urinary tract symptoms

24
Q

What are the storage symptoms associated with BPH?

A

Frequently passing urine
Feeling the bladder is full (urgency)
Waking up in the night to pass urine (nocturia)
Urge incontinence

25
Q

What are the voiding symptoms associated with BPH?

A
Hesitancy (waiting for stream to start)
Weak stream 
Stream starts and stops 
Dribbling at the end of urination 
Sensation of incomplete bladder emptying
26
Q

What are the different findings you would find on a DRE for BPH and prostatic cancer?

A

BPH - prostate enlarged but smooth

Cancer - nodules present on prostate

27
Q

Why does PSA level increase in BPH?

A

Epithelial cells are dividing as the prostate enlarges

More epithelial cells are secreting PSA

28
Q

Why must you wait to take PSA levels until some time after ejaculation?

A

Ejaculation can raise PSA by 20%

29
Q

What is the pathogenesis of BPH?

A

As you age, you pee more, each causing trauma to the urethra resulting in inflammatory response
This causes the release of more testosterone
Testosterone is converted into DHT
DHT signals growth factors signalling
This causes an enlargement in the transitional zone

30
Q

What are the two main types of treatment for BPH?

A

Alpha1 adrenergic receptor antagonists

Anti-androgen (5-alpha reductase inhibitors)

31
Q

How are alpha 1-adrenergic receptor antagonists used to treat BPH?

A

Inhibit the binding of noradrenaline to alpha 1 Receptors in the internal urethral sphincter
This causes relaxation of the sphincter
Relaxation around the bladder neck
This reduces urethral occlusion

32
Q

What is a major side effect of using alpha 1 -adrenergic receptor antagonists and why?

A

Postural hypotension

Arterioles have alpha receptors, so blocking these can lead to relaxation of arterioles

33
Q

Give some examples of alpha-1adrenergic receptor antagonists?

A

Tamsulosin
Alfuzonsin
Doxazosin

34
Q

How are 5alpha reductase inhibitors used to treat BPH?

A

Block conversion of testosterone to DHT
This slows the growth of stromal and epithelial prostate cells

Drug also promotes apoptosis

35
Q

Give some examples of 5alpha reductase inhibitors?

A

Finasteride

Dutasteride

36
Q

What is transurethral resection of the prostate (TURP)?

A

Surgical procedure used to treat BPH
Resectoscope is inserted into the urethra and to the prostate
Electric current is used to heat the loop of the wire
The loop is then used to remove part/all of the prostate
After, saline solution is pumped into the bladder to flush away the pieces of prostate removed

37
Q

What is holmium laser enucleation of the prostate (HOLEP)?

A

Surgical procedure used to treat BPH
Alternative to TURP
Uses laser to separate excess tissue from the prostate

38
Q

What kind of tumour is a prostatic cancer?

A

Adenocarcinoma

39
Q

How are prostate cancers grouped into risk categories?

A

Low risk: Gleason score 6, PSA <10ng/ml
Intermediate risk: Gleason score 7, PSA 10-20ng/ml
High risk: Gleason score 8-10, PSA > 20ng/ml

40
Q

What is the Gleason score?

A

The grading system to determine the aggressiveness of prostate cancer

41
Q

Where does prostatic cancer metastases to?

A

Liver

Lungs

42
Q

What is brachytherapy?

A

Treatment for prostatic care
Implant radioactive seeds into prostate
These deliver high dose of radiation to prostate gland and cancer

43
Q

What is hydronephrosis?

A

Dilation of the renal pelvis and calyces due to excessive fluid