Block 10 Flashcards
Functions of urinary system
- maintain water balance
- maintain salt balance
- metabolise Vit D
- regulate blood glucose lvls
- gluconeogenesis
- EPO production
- renin release
- excretion of metabolic waste products
2 layers of Bowman’s capsule
Parietal - simple squamous epithelium
Visceral - simple squamous epithelium w inner layer of podocytes on basement membrane which sits on fenestrated endothelium of glomerulus
Key characteristic of both nephrotic + nephritic syndrome
disruption to glomerular filtration barrier causing some degree of proteinuria
Half life
Half-life of a drug (T ½) is the time necessary to halve the plasma concentration
BPE
Benign prostatic enlargement
Most common cancer in men in UK
Prostate cancer
Hesitancy
difficulty initiating urination
if GFR too high…
- not enough time for reabsorption
- [NaCl] in filtrate high
Name of glands lying either side of the distal urethra in females
Skene’s glands
- homologous to male prostate
General histology of proximal convoluted tubule (PCT)
- simple cuboidal epithelium
- microvilli on apical surface – increase SA for reabsorption
- high number of mitochondria – produce ATP needed for reabsorption
- highly infolded basolateral membrane
Cells involved in tubulo-glomerular feedback
Macula densa cells of DCT
Clinical hallmarks of nephrotic syndrome (4)
- Proteinuria
- Oedema
- Lipiduria
- Hyperlipidemia
Normal blood pH
7.34 - 7.38
Most common cause of intrarenal AKI
Acute tubular necrosis
Receptors in the detrusor muscle that get activated stimulating bladder contraction
M3 muscarinic receptors
Briefly explain the myogenic mechanism of regulating glomerular filtration
Drop in mean arterial BP:
- detected by SMCs in afferent arterioles triggers vasodilation
- increased blood flow to glomerulus
- increased filtration
Increase in mean arterial BP:
- detected by SMCs in afferent arterioles triggers vasoconstriction
- decreased blood flow to glomerulus
- decreased filtration
Why can’t negatively charged molecules pass through the filtration membrane?
proteins in filtration membrane are -ve so repel -ve charged molecules
Cortical nephron capillary beds
peritubular capillaries
Azotemia
increased retention of urea and creatinine
Mesangial cells
cells in filtration membrane
can contract to help regulate rate of filtration through glomerulus
First site of water reabsorption in nephron
PCT
[NaCl] in filtrate directly varies with
filtrate flow rate
Preclinical disease state
- starts w the onset of the disease process
- AND lasts until signs and symptoms appear
Pedicels
tiny projections of podocytes which interdigitate to form filtration slits
Why can a female bladder not hold as much urine as a male bladder?
Uterus takes up space and crowds out some of bladder volume
Dysuria
pain when urinatining
3 main components of filtration membrane
- fenestrated capillary endothelium
- basement membrane w -ve charged proteins
- pedicels of podocytes forming filtration slits
Main general cause of intrarenal failure
damage to nephron tubules, glomerulus or interstitium
Structural damage to the basement membrane and podocytes causes
Nephrotic syndrome
Hydronephrosis
high pressure in bladder can push urine back up ureters into kidneys=> causes renal pelvises to expand
How does the body try to compensate for massive renal protein loss in nephrotic syndrome?
reactive hepatic protein synthesis - liver tries to ,make more plasma proteins
BOO
bladder outflow obstruction
Arterial supply to prostatic urethra
inferior vesical artery
Site of ADH release
posterior pituitary
Structures of kidney the transpyloric plane crosses
- hilum of L kidney
- superior pole of R kidney
How does hypoalbuminemia lead to oedema?
- decreased serum albumin
- decreased colloid/oncotic pressure
- fluid leaves blood + enters tissue
=> oedema
Pyruria
WBCs in urine
Renal clearance
volume of plasma that is cleared of a substance in 1 min (ml/min)
Bicarbonate lvls greater than 26mEq/L
metabolic alkalosis
Bicarbonate lvls below 22mEq/L
metabolic acidosis
Proteinuria
protein loss of >3.5g per 24hrs in urine for NEPHROTIC syndrome
if less 3.5g per day => NEPHRITIC
Commonest cause of end-stage renal disease (ESRD) in the western world
Diabetic nephropathy
painless haematuria is indicative of:
Bladder transitional cell carcinoma
Transpyloric plane crosses the
Superior pole of the R kidney and hilum of L kidney
at vertrebral level L!
Muscles in medial aspect od kidney
Psoas major + psoas minor
Muscles posterior to kidney
Iliacus
R renal artery =
LONGER than left
Renal arteries arise from
the lateral aspect of the abdominal aorta
Interlobular arteries enter the
RENAL CORTEX
Ureters pierce bladder at angle
create antegrade flow of urine
Hypogastric nerve
=> parasympathetic nerve contracts detrusor muscle creates high P
Rugae stretch when distended
bladder can strectch out leave pelvis and enter the suprapubic area
Females don’t have internal urethral sphincter
males have this to prevent retrograde movement of ejaculate into urine
quite a few pins -> will likely want you to identify the muscles thst make up the leavtor asni
Could I please peek? menonemonic
Ischioanal fossa
allows rectum to expand during defecation and pudendal nerve also contained within here
