PHYS 2.5 Intro to Renal blood flow and glomerular filtration rate Flashcards
Glomerular filtration barrier
three layers?
glycocalyx does what
governs and acts as what?
proteins that bind to glycocalyx?
a barrier?
response to inflammation?
- The endothelial glycocalyx governs transcapillary fluid exchange and acts as a biomechanical sensor
- proteins that bind to the glycocalyx include proteins involved in cell attachment, migration, differentiation, morphogenesis, blood coagulation, lipid metabolism, and inflammation
- can be a size barrier to albumin filtration
- (fiber mesh with pores)
- glycocalyx-degrading enzymes such as hyaluronidase, heparanase endosulfatases, and proteinases. (in response to disease process)
What passes the filtration barrier?
Freely filtered?
Not freely filtered?
FIltered components depend on size and charge
Tamm-Horsfall protein
Cells in the thick ascending limb produce Tamm-Horsfall glycoprotein and secrete it into the tubular fluid. protein reabsorption is “upstream” of thick ascending limb Tamm-Horsfall appears in urine
Need more than trace proteins to be indicative of disease
what can happen with a damaged filtration barrier?
Both can be due to a damaged filtration barrier
Hematuria
- alport syndrome (collagen in basement membrane mutation)
Proteinuria
- increase in urinary protein
- increase permeability of glomerular capillaries
- loss of normal podocyte structure ( thinning of foot process)
Cortex vs medulla for difference of the microcirculation
Cortex has a much higher blood flow than the medulla
the outer medulla has a little more than the inner medulla
Kidneys receive how much blood?
microcirculation consists of what capillary networks?
the peritubular capillaries can be further broken down into?
Renal blood flow
renal fraction
glomerular caps pressure? favors?
peritubular caps pressure? favors?
during exercise?
filtered load?
FIltered load of X = (Plasma concentration of X) (GFR)
filtered load= amount of substance X that is filtered into the bowmans space in a given amount of time
Actual filtereed depends on amount that is bound (wont get filtered) and amount free (will get filtered)
Urinary excreation=
Tubular reabsorption=
what if excretion > filtration?
Urine excretion rate of x?
Renal clearance
rate at which?
formula?
for a v= 1.44 L/day is the same as 1 mL/min
Glomerular filtrate
GFR
formula for FF?
how to calculate GFR from RBF and vise versa
glomerular filtration rate
RBF- renal blood flow?
RPF- renal plasma flow
FF-filtration fraction
RBF approx RPF
FF what is it?
how does the amount effect blood pressure and oncotic pressure?
with more RBF out filtered means a more concentrated arteriole so more oncotic pressure
changes to FF?
filtered load vs filtration factor
basic processes of urine formation
what processes will lead to urine formation
(where are things filtered etc)
Ex of net reabsorption of Na
filtered load
reabsorption equals?
excretion
how these 3 interplay together.
variables at play?
percentage of Na reabsorbed?
renal clearance link to GFR?
this is true when?
inulin tells us what?
why?
creatinine clearance
