case 7 - introduction to the kidney Flashcards
what is the function of the kidney via the maintenance of the extracellular fluid volume
via sodium and water
what is the endocrine secretion function of the kidney
renin-angiotensin system
erythropoeitin
vitamin D - calcium regulation
what are the different parts of the nephron
renal corpuscle
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
what does the renal corpuscle do
produces filtrate
what does the loop of henle do
further reabsorption of water (descending limb)
And both sodium and chloride ions (ascending limb)
what does the distant convoluted tubule do
secretion of ions, acids, drugs and toxins
variable reabsorption of water, sodium ions and calcium
what does the collecting duct do
variable reabsorption of water and reabsorption or secretion of hydrogen and bicarbonate ions
what does the papillary duct do
delivery of urine to minor calyx
what are the different parts of the collecting system
collecting duct
papillary duct
where does filtration happen
in the nephron
where does selective reabsorption happen
in the proximal convoluted tubule
where does secretion happen
in the collecting duct
what surrounds the nephron
the vasa recta
what happens in the vasa recta
this is where the substances that are reabsorbed from the tubular fluid and that we need to retain, re-enter the blood supply and then drain into the vein to eventually come back and leave via the hillum into the renal vein to then be returned to the general circulation
what is normal cardiac output
5 litres per minute
how much of the cardiac output do the kidneys recieve
20% - 1L per minute
what is the equation for glomerular filtration rate
GFR = Kf × [PGC - (PBC + p(pie)GC)]
what is Kf
filtration coefficient
what is PGC
glomerular capillary hydrostatic pressure
- favours filtration
what is pie(GC)
glomerular capillary oncotic pressure
- opposed filtration
what is PBC
Bowman’s capsule hydrostatic pressure
- opposes filtration
what should oncotic pressure be
0
where does blood enter the glomerulus through
the afferent arteriole and then enters the glomerular capillary network
where does filtration occur
in the ball of capillary
what is part of the filtration barrier
podocytes are part of the filtration barrier - stops larger molecules from leaving the blood and entering the tubular fluid
what is the cut off point at which the physical barrier prevents filtration
approximately the size of albumin
what is the charge in the membrane
it has negative charge - there is also a charge barrier
do the GFR in notes in the introduction to kidney example!!!
the next few flashcards are explaining the mechanism of autoregulation
what happens as blood pressure in the renal artery increases
there is a corresponding increase in the resistance to flow of the afferent arteriole.