22. CKD background science Flashcards
what is the functional unit of the kidney
nephron
where is blood initially filtered in the nephron and where does it enter and exit
glomerulus
afferent and efferent arteriole
in the glomerulus there are 3 layers of filtration, name them
vascular endothelium
glomerular basement membrane
podocytes
where are the mesangial cells found in the glomerulus
in the centre stalk of the glomerulus
in diabetic nephropathy what causes vasoconstriction of the;
efferent arteriole
afferent arteriole
efferent arteriole due to hyperglycaemia
afferent arteriole due to HTN
why can having hyperglycaemia lead to nephron ischemia
the blood supply to the nephron itself is via branches that come off the effect arteriole and hyperglycaemia causes narrowing of the efferent arteriole
in diabetic nephropathy why is there initially and increased GFR
there is increased glomerular pressure due to HTN and RAS activation
in diabetic nephropathy what causes for there to be detectable proteinuria (albumin) and why
increase in glomerular pressure and barotrauma of the mesanigium
- mesangium expands which means that podocyte foot plates eventually are moved further apart and so have fenestrations (gaps) which allow proteins to slip into the tubules
in diabetic nephropathy what does nephron ischaemic lead to
microhaematuria and kidney failure (reduced urine output)
what is the treatment for diabetic neuropathy
ACEi
anti-diabetic medication
tell me about the gross anatomy of the kidney
- is it retroperitoneal or intraperitoneal
- where does it lie over
- where are the nephrons found
- what is the blood supply
- how many nephrons does each kidney contain
- retroperitoneal
- transverse processes of T12-L3 (right kidney sits lower due to the liver)
- renal cortex
- renal artery which carrie 20-25% of the total cardiac output
- 1 million
what is the distribution of portico-nephrons and juxtamedullary nephrons
• 85% are cortico-nephrons which means lay in the cortex and only have a short loop going into the medulla
• 15% are juxta-medullary nephrons which sit in inner 1/3rd of cortex and have a long loop extending into the medulla
o After the age of around 35 there is 1% loss of function of nephrons due to nephron loss due to aging
what is the Renal corpuscle made up of
glomerulus bowman capsule capsular space capillaries covered in podocytes mesanigal cells
what is the function of the corpuscle
acts like a sieve, produces an ultrafiltration of the plasma into the bowman’s capsule and then into the PCT
which part of the tubular structure contains many Irish boarder cells which contain microvilli and mitochondria to carry out the primary function of reabsorption
convoluted part of the tubule
