Problems with the male reproductive system Flashcards
What are the rough dimensions of the prostate
342
In adult male, approx 20g
What is the function of the prostate
Makes up 30% of seminal fluid- alkaline secretions to neutralise acidity of vagina
Secretes anticoagulant to ensure sperm can swim effecitvely
Name the 3 zones of the prostate
Transitional zone
Central zone
Peripheral zone
Describe the peripheral zone of the prostate
Makes up 70% of the prostate, runs around the periphery and surrounds urethra at inferior border
Describe the central zone of the prostate
Makes up 25% of the prostate, surrounds the ejaculatory ducts and vas deferens. Lots of connective tissue
Describe the transition zone of the prostate
Makes up 5% of the prostate. Surrounds more proximal part of urethra as it exits bladder. Transition from central zone to glandular tissue in periphery
Which zone of the prostate is most effected by
a) prostate cancer
b) BPH
a) peripheral zone
b) transitional zone
How does the prostate appear/ feel in benign prostatic hyperplasia
Appears significantly bigger but retains smooth surface throughout
Nodules are present inside but can’t be felt externally
How does the prostate appear/ feel in prostatic cancer
Feels like a nodule as cancer usually arises in prostatic zone
What cellular changes that happen in advanced age result in BPH? Why is advanced age thought to be linked to this
Increased cell proliferation and decreased apoptosis
Happens due to lifelong exposure to testicular androgens
What happens in the stroma of prostate
Testosterone is converted to estradiol by aromatase
Binds to oestrogen receptor alpha
Causes fibroblasts and SMC to proliferate
Hypertrophy and hyperplasia in connective tissue of transitional zone
What causes epithelial cell apotosis in prostate
In the epithelial cells estradiol leaks across
Testosterone converted to DHT and binds to receptor
Compression of which structure produces symptoms of benign prostatic hyperplasia
Urethra
What % of people with the symptoms of BPH also have it histologically
50
How can BPH be diagnosed?
- History
- Digital rectal exam
- Visualisation of prostate, accurate idea of measurments and regions
What do blood tests for BPH look for
PSA which is an anticoagulant
If <10ng/ml due to BHP not cancer
How do alpha adrenergic blockers treat BHP
Relaxes smooth muscle in bladder neck improving flow rate
How does 5 alpha reductase inhibitor work to treat BHP
Blocks the conversion of testosterone to its active form
What is transurethral resection
Goes through urethra and cuts out transitional zone
What is open prostatectomy
Inner core of prostate is shelled out
What is laser ablation
Laser ‘cooks’ off transitional zone
What is urolift
Procedure goes through urethra and ties prostate to open it up so urethra is widened
Describe the structure of the superficial inguinal ring
Area where the vas deferens is coming up through the testes and going through abdomen
Describe the deep inguinal ring
Where vas deferens comes in, external iliac vessels are found on the inside
What vessels come off the external iliac vessels
Inferior epigastric artery and vein
How do you differentiate between direct and indirect hernias
Medial to inferior epigastric artery= direct
Lateral= indirect
When do direct hernias occur
Acquired due to age
When do indirect hernias occur
Associated with failure of the inguinal canal to close properly after passage of the testes in utero
Defect that intestine can follow through
Which side do indirect hernias usually occur on and why
Right
Right testes is larger and descends later
2 definitions of erectile dysfunction
- Inability/ inconsistenty in having an erection
- Inability to maintain an erection
What are some causes of erectile dysfuntion
Diabetes Vascular disease Radical surgery Spinal cord injury Endocrine disorders MS
What vessel drains the penis
Dorsal deep vein
Describe movement of blood in the penis when it is flaccid
Cavenosal artery bring blood in but it drains quickly
Describe blood movement in the penis when its erect
Inflow increases expanding the sinusoids compressing the outflow
Describe parasympathetic control of erection
- Parasympathetic neurone release NO
- NO diffuses across to smooth muscle and into smooth muscle cell
- Binds to soluble guanylyl cylase producing cyclic GMP which causes smooth muscle relaxation
- Vasodilation of sinusoids= erection
Describe sympathetic control of erection
Release noradrenalin
Binds to alpha 1
Contraction of sinusoids
How does viagra work?
Prevents breakdown of cGMP
Causes relaxation for longer and increased erection
Does viagra work for people with spinal cord issues
No because it requires sexual arousal to work
What is Peyronies disease
Bent penis
Caused by scar tissue in the corpus cavernosus leading to it bending
What is variocele
Varicose veins on scrotum, always on the left testes because testicular vein on left side doesn’t drain properly
