Glomerular Filtration Rate Flashcards
What is the definition of glomerular filtration rate (GFR)?
Glomerular filtration rate (GFR) is the volume of filtrate produced per minute by the kidneys.
Why is GFR an important measure of kidney function?
GFR is an important measure of kidney function because it indicates how well the kidneys are filtering blood.
What are the normal values for GFR in healthy adults?
Normal GFR values for healthy adults are approximately 90-120 mL/min/1.73 m².
Which equation is commonly used to estimate GFR in clinical practice?
The MDRD (Modification of Diet in Renal Disease) equation and the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation are commonly used to estimate GFR.
How does the hydrostatic pressure in the glomerular capillaries affect GFR?
Increased hydrostatic pressure in the glomerular capillaries increases GFR.
What role does the colloid osmotic pressure in the glomerular capillaries play in GFR?
Colloid osmotic pressure in the glomerular capillaries opposes filtration, thereby reducing GFR.
How does Bowman’s capsule hydrostatic pressure influence GFR?
Increased Bowman’s capsule hydrostatic pressure decreases GFR.
What effect does systemic blood pressure have on GFR?
Increased systemic blood pressure generally increases GFR, while decreased blood pressure reduces GFR.
How does the afferent arteriole diameter affect GFR?
Dilation of the afferent arteriole increases GFR by increasing blood flow into the glomerulus.
How does the efferent arteriole diameter affect GFR?
Constriction of the efferent arteriole increases GFR by increasing pressure within the glomerulus.
What is the role of the juxtaglomerular apparatus in regulating GFR?
The juxtaglomerular apparatus regulates GFR by controlling renin release and thus affecting arteriole diameter and blood pressure.
How does the renin-angiotensin-aldosterone system (RAAS) influence GFR?
The RAAS system increases GFR by constricting the efferent arteriole and increasing systemic blood pressure.
What is the effect of sympathetic nervous system activation on GFR?
Activation of the sympathetic nervous system decreases GFR by constricting afferent arterioles and reducing renal blood flow.
How does the filtration coefficient (Kf) impact GFR?
The filtration coefficient (Kf) affects GFR by determining the permeability and surface area available for filtration.
What is the role of mesangial cells in regulating GFR?
Mesangial cells regulate GFR by contracting or relaxing to alter the surface area available for filtration.
How do plasma protein levels affect GFR?
Low plasma protein levels increase GFR by reducing colloid osmotic pressure in the glomerular capillaries.
What is the relationship between GFR and renal plasma flow (RPF)?
GFR is directly proportional to renal plasma flow (RPF); increased RPF generally increases GFR.
How does diabetes mellitus affect GFR?
Diabetes mellitus can initially increase GFR but may lead to decreased GFR over time due to kidney damage.
How does hypertension influence GFR?
Hypertension can increase GFR initially but may cause damage that leads to decreased GFR over time.
What is the effect of dehydration on GFR?
Dehydration decreases GFR due to reduced plasma volume and renal blood flow.
How does aging impact GFR?
Aging generally decreases GFR due to a reduction in the number of functional nephrons.
How does acute kidney injury (AKI) affect GFR?
Acute kidney injury (AKI) decreases GFR due to sudden loss of kidney function.
What is the impact of chronic kidney disease (CKD) on GFR?
Chronic kidney disease (CKD) leads to a progressive decline in GFR over time.
How do diuretics affect GFR?
Diuretics can affect GFR by altering plasma volume and renal blood flow.
