Renal Physiology
Renal Physiology
This study guide reviews the following topics:
1. Filtration Mechanisms
2. Measuring renal blood flow
3. Mechanisms of tubular transport
4. Factors affecting renal vascular tone
5. Renin Angiotensin Aldosterone System
Preview
“Remember, you are braver than you believe, stronger than you seem, and smarter than you think”
Winnie the Pooh
@barbstudy2021
, Renal Physiology
Function of kidneys: by:
❊ Regulation of extracellular fluid volume
❊ Elimination of toxins
❊ Homeostasis of osmolarity + ion concentrations
❊ Hormone production
(site of interaction between these 2 points)
Blood vessels + renal tubes = nephrons
Blood flow in kidneys
renal arteries à interlobar arteries à arcuate arteries à interlobular arteries à afferent arterioles
Tubular system: starts at glomerulus and extends to the collecting ducts
Cortical: Filters 80% of blood supply cortex
Nephrons
Juxtamedullary: Filters 20% of blood supply
Medical interventions if the kidney does not regenerate after damage:
1. Renal dialysis (machine to remove waste + excess fluid)
2. Kidney transplant (operation to get a healthy person’s kidney) medulla
Basic Mechanisms of The Nephron
Renal Blood Flow:
1. Filtration
Requires 20% cardiac output Figure 1: schematic representation of the
2. Secretion 1000ml/min tubular system
3. Re-absorption OR
4. Excretion 500ml/min/kidney
Burning Question!!!
Which part of the kidney (cortex/medulla) is more susceptible to ischemia?
Answer: Medulla
Why? The medulla is further away from the arterial blood supply. This means that blood flows to the
medulla slowly and there is decreased perfusion (oxygen and nutrients supply) in this area. This also
means that it is more susceptible to Renal Tubular Damage.
Measuring Renal Blood Flow
1. Clearance Method 2. Ultrasonic Flow Meter 3. Laser Doppler Flowmetry
Para-aminohippuric acid (PAH) is Electrical Pulse used to Shine a frequency beam over a
injected into the body and taken measure renal blood flow. blood vessel and use the
up by the proximal tubule. Doppler Effect to measure renal
100% of it is excreted and thus is blood flow.
effective in measuring renal blood
flow rate.
@barbstudy2021
Renal Physiology
This study guide reviews the following topics:
1. Filtration Mechanisms
2. Measuring renal blood flow
3. Mechanisms of tubular transport
4. Factors affecting renal vascular tone
5. Renin Angiotensin Aldosterone System
Preview
“Remember, you are braver than you believe, stronger than you seem, and smarter than you think”
Winnie the Pooh
@barbstudy2021
, Renal Physiology
Function of kidneys: by:
❊ Regulation of extracellular fluid volume
❊ Elimination of toxins
❊ Homeostasis of osmolarity + ion concentrations
❊ Hormone production
(site of interaction between these 2 points)
Blood vessels + renal tubes = nephrons
Blood flow in kidneys
renal arteries à interlobar arteries à arcuate arteries à interlobular arteries à afferent arterioles
Tubular system: starts at glomerulus and extends to the collecting ducts
Cortical: Filters 80% of blood supply cortex
Nephrons
Juxtamedullary: Filters 20% of blood supply
Medical interventions if the kidney does not regenerate after damage:
1. Renal dialysis (machine to remove waste + excess fluid)
2. Kidney transplant (operation to get a healthy person’s kidney) medulla
Basic Mechanisms of The Nephron
Renal Blood Flow:
1. Filtration
Requires 20% cardiac output Figure 1: schematic representation of the
2. Secretion 1000ml/min tubular system
3. Re-absorption OR
4. Excretion 500ml/min/kidney
Burning Question!!!
Which part of the kidney (cortex/medulla) is more susceptible to ischemia?
Answer: Medulla
Why? The medulla is further away from the arterial blood supply. This means that blood flows to the
medulla slowly and there is decreased perfusion (oxygen and nutrients supply) in this area. This also
means that it is more susceptible to Renal Tubular Damage.
Measuring Renal Blood Flow
1. Clearance Method 2. Ultrasonic Flow Meter 3. Laser Doppler Flowmetry
Para-aminohippuric acid (PAH) is Electrical Pulse used to Shine a frequency beam over a
injected into the body and taken measure renal blood flow. blood vessel and use the
up by the proximal tubule. Doppler Effect to measure renal
100% of it is excreted and thus is blood flow.
effective in measuring renal blood
flow rate.
@barbstudy2021
