Genitourinary

Question 1

what are the functions of the kidney?

Answer 1

• filter or secrete waste substances
• retain albumin and circulating cells
• reabsorb glucose, amino acids and bicarbonates
• control BP, fluid status and electrolytes
• activates 25 hydroxyvitamin D
• synthesis erythropoietin

Question 2

what is a normal eGFR?

Answer 2

120ml/min = 7.2L/h, 170L/day

Question 3

what K+ modifying renal medication causes hypokalaemia?

Answer 3

loop diuretics and thiazide diuretics

Question 4

what is erythropoietin?

Answer 4

a hormone that produces haemoglobin in response to tissue hypoxia

Question 5

what is 25-hydroxy vitamin D hydroxylated to?

Answer 5

1,25-dihydroxy vitamin d (calcitriol)

Question 6

what are the actions of calcitriol

Answer 6

• increases ca2+ and phosphate absorption from the gut
• increases phosphate absorption to a lesser extent
• suppresses parathyroid hormone
• deficiency results in secondary hyperparathyroidism - low vitamin D results in low ca2+ and phosphate resulting in increased PTH which causes ca2+ and phosphate to leech out of bone. PTH also acts on osteoclasts by increasing their activity and bone turnover

Question 7

what makes up the upper urinary tract?

Answer 7

kidneys and bladder

Question 8

what makes up the lower urinary tract?

Answer 8

bladder, bladder neck, prostate gland, urethra and urethral sphincter

Question 9

what is the function of the lower urinary tract?

Answer 9

to convert the continuous process of excretion (urine production) to an intermittent, controlled volitional process - micturition

Question 10

what are the features of the lower urinary tract?

Answer 10

• low pressure and insensible storage of urine of adequate capacity
• prevent leakage the urine stored
• allow rapid, low pressure voiding at an appropriate time and place

Question 11

describe urinating (voiding)

Answer 11

• pontine micturition centre stimulates excitatory control to detrusor nucleus and inhibits Onuf’s nucleus
• signal is transmitted from spinal root S3,4,5 via the parasympathetic nervous system resulting in contraction of detrusor muscles and relaxation of the urethra

Question 12

describe the process of storage (stopping urination)

Answer 12

• pontine storage centre stimulates and sends inhibitory signals to detrusor muscles and excitatory signals to Onuf’s nucleus
• signal is transmitted from spinal root T10, L1 + 2 via the sympathetic nervous system and this results in the relaxation of the bladder and contraction of the urethral sphincter

Question 13

what happens if the cord is cut above s2,3,4

Answer 13

urination only occurs when the bladder is full but the descending pathway will not be able to inhibit this with their mind as descending pathway will be destroyed

Question 14

is urinating cholinergic or noradrenergic?

Answer 14

cholinergic (parasympathetic)

Question 15

is storage cholinergic or noradrenergic?

Answer 15

noradrenergic (sympathetic)

Question 16

what kind of epithelium does the bladder have?

Answer 16

urothelium (transitional epithelium)

Question 17

describe urothelium

Answer 17

highly specialised stratified, 2-7 cells thick
umbrella structure that is impermeable so cannot resorb urine
able to fold and unfold to increase volume