Renal Clearance And GFR Flashcards
What is clearance
Rate at which substances are removed from plasma
What is renal Clearance
Volume of plasma completely cleared of a substance by the kidneys per unit time
What does high rental clearance means
High removal of substances
What is the equation for renal clearance
C = (urine concentratiin of substance * urine flow rate ) / plasma concentration of substance
Is albumin filtered across glomerular capillaries
No
What is the renal clearance of albumin
0
Renal clearance of glucose
0
Why is Renal clearance of glucose zero
Glucose is completely reabsorbed back into the bloodstream
What substances clearance measures the GFR Because it is neither a reabsorbed nor secreted after being filtered
Inulin
What is the glomerular marker
Inulin
What is the clearance ratio formula
Clearance of substance / clerance of inulin
What does a clearance ratio of one means
Means that the substance is also a glomerular marker so neither reabsorbed not secreted
What does a clearance ratio inferior to one means
the substance is either not filtered or it is filtered and then reabsorbed
What does the clearance ratio of more than one means
It means that the substance is filtered and then secreted
What is an ultra filtrate
Fluid that is filtered from blood at the Bowman space and is composed of water , small solutes of blood but no proteins and blood cells
What determines the rate of glomerular filtration and characteristics of the glomerular filtrate
The physical characteristics of the glomerular capillary walls
What do you find in the endothelium of the glomerular capillary
Pores 70-100nm in diameter
What are the role of pores in the endothelium of the glomerular capillary
To allow filtration across this layer of fluids dissolved solute’s in plasma proteins and block blood cells
What is the most significant barrier of the glomerular capillary
The multilayered basement membrane because does not allow filtration of plasma proteins
What specialized so do you find in the epithelium of the glomerular capillary
Podocytes
Filtration slits
Is inulin endogenous
No must be injected iv
LWhat is the closest substance to the perfection of inulin As a glomerular marker
Creatinine
Why is creatinine not so much perfect as in
One part of it is secreted so clearance slightly over estimates the GFR
What is the positive side of creatinine
Endogenous substance so no need for injection
