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Systems Physiology > Renal Physiology Part 1 (annotated) > Flashcards

Renal Physiology Part 1 (annotated) Flashcards

1
Q

What are the main functions of the kidney?

A

Kidney functions:

  1. Maintain constant body fluid volume
  2. Maintain constant fluid composition
  3. Endocrine organ
  4. Acid-base balance
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2
Q

What is the function of osmosis? What is osmotic pressure? What is the equation for osmolarity?

A

Osmosis- movement of water across cell membrane
The driving force for movement of water is Osmotic pressure difference across cell membrane
osmotic pressure- determined by the number of solute particles in solution
Osmolarity= Concentration x number of Dissociable particles
MOsm/L=mmol/L (milimolar) x number of particles /mol
ex: if have 150mmol/L NaCl = 150 x 2(2 particles in salt)- 300 mOsm/L

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3
Q

What happens if one compartment of 300 Osmoles of liter and another compartment has 100 mOsmoles per liter. Where does water go to?

A

Water goes towards compartment that is MORE Concentrated (300 osmoles). Since the more concentrated compartment has got greater osmolarity, then water moves there.

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4
Q

What is oncotic pressure?

A

Oncotic pressure- the osmotic pressure generated by LARGE molecules like PROTEINS (has pi symbol).
It is an important force of kidneys which regulate fluid movement across glomerulus and peritubular capillaries

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5
Q

How is body fluid compartmentalized?

A

Body fluid is compartmentalized into Extracellular and intracellular compartments
The intracellular compartment: 2/3 of total fluid
Extracellular compartment: 1/3 of total fluid
cell membrane divides intracellular and extracellular part.
Extracellular fluid compartment further divided into Plasma (1/4; blood vessels, vascular) and interstitial compartment (3/4, fluid between cells in tissue)

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6
Q

How much water makes up body weight? How much of intracellular vs extracellular makes up the body weight?

A

60% total body water makes up body weight
Total body water can be divided into intracellular fluid (40% of body weight;2/3) and extracellular fluid (20% of body weight)
extracellular fluid divided into interstitial fluid (3/4) and plasma (1/4)

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7
Q

How do kidneys maintain extracellular volume? What happens if you change extracellular fluid?

A

Kidneys monitor extracellular fluid volume. If you change extracellular fluid, you will also change intracellular fluid due to osmotic pressure that act between two compartments
The kidneys function to alter/regulate plasma volume
if you change plasma fluid volume you impact interstitial fluid as well (to maintain constant body fluid volume)

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8
Q

What is occurring in ECF/ICF when water is ingested?

A

A) Increasing in intracellular fluid (ECF shift right). Extracellular fluid increases to Left of graph. increase in intracellular fluid and decrease in osmolarity. Increase in extracellular fluid and increase in osmolarity.
Also equal change in both ECF/ICF due to DRINKING WATER. Drink water: ECF increases, ICF also increases to equilibrate, and osmolarity decreases (dilute compartment with water)

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9
Q

What happens to ECF when you drink water?

A

Drink water: ECF increases, ICF also increases to equilibrate, and osmolarity decreases (dilute compartment with water)

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10
Q

What is happening to ECF in graph for B (hypertonic solution) ?

A

B) ECF volume increases, Osmolarity INCREASES and ICF (intracellular) volume DECREASED
Due to person being injected with HYPEROSMOTIC solution, so it will go to extracellular fluid compartment(plasma, blood) and increase its volume.
Hyperosmotic will Increase osmolarity, and pull fluid from ICF and ECF and ICF will equilibrate.

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11
Q

What would happen to ECF if you drank Gatorade (isosmotic fluid; salts, ions)?

A

If you drank Gatorade (isosmotic- same osmotic pressure as blood):
ECF volume would go up. Osmotic pressure would stay the same.
Since your osmotic pressure did not change, there will be no movement of substance into ICF (only added volume).

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12
Q

What is happening to ECF in graph for C (Dehydration)?

A

Both ECF and ICF have DECREASED and Osmolarity has increased.
This occurs due to DEHYDRATION: you are Losing volume, so you lose water. If you lose more water than, you lose ions, than osmolarity increases.

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13
Q

What is happening to ECF and ICF in graph for D (hyposmotic saline)?

A

You inject someone with hyposmotic saline solution; the ECF increase. since used hyposomotic solution, the Osmolarity DECREASES
water- freely permeable; more water than you have solutes so you must equilibrate between ECF and ICF (expansion of ICF)

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14
Q

Describe the structure of a kidney. What is the path of fluid in kidney

A

Kidney- bean shaped; that is divided into outer cortex and inner medulla (pyramid). You have minor calyxes leading to major calyx.
Fluid drain from cortex to medulla to minor and major calyxes to the renal pelvis and into ureter which leads to the bladder.

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15
Q

Describe the blood supply to kidney

A

Blood supply to kidney:
-1 renal artery that branches out into smaller arteries to arterioles
Blood is collected through veins into renal veins.
one renal artery goes into kidney and 1 renal vein comes out of kidney.

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16
Q

What is the structural, functional unit of kidney?

A

NEPHRON.

1 million nephrons per kidney (x 2- kidneys).

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17
Q

What are the nephron segments?

A

Nephron segments are divided into outer cortex and inner medulla
Nephron starts with Afferent arteriole which goes toward glomerulus.
Glomerulus is a tuft of capillaries. the capillaries give rise to efferent arteriole
Then fluid filtered out of glomerulus into bowman’s capsule then into proximal convoluted tubule into thin descending loop of Henle. Then Thin ascending limb of Loop of Henley and into Thick ascending limb of loop of Henley.
Macula densa- special region that separates area between thick ascending limb and thick descending limb
Distal convoluted tubule then becomes known as cortical collecting duct

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18
Q

What is the role of loop of Henle?

A

Loop of Henle: Hairpin loop that comes back to afferent and efferent arteriole(V shape). Macula densa goes in and out of wall. macula densa is where thick ascending limb is.
afferent arteriole and efferent arteriole is very close to macula densa due to hairpin loop

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19
Q

What are the juxtaglomerulus cells?

A

justaglomerulus cells (aka a Granular cells) are close to macula densa and glomerulus.

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20
Q

Describe the components of the juxtaglomerular apparatus. What is the function of some structures?

A

Juxtaglomeruluar (JG) appartus

  • portion of tubule where the thick late ascending limb of Henle’s loop courses between arterioles
  • Made up of 2 cell types:
    1. Granular cells- differentiated smooth muscles in the walls of arterioles
    2. Macula densa cells

granular cells secrete hormone RENIN. Macula Densa contributes to CONTROL of Glomerular filtration rate and to secretion of renin.

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21
Q

Describe the blood supply of nephron

A

Blood supply:
comes from renal artery into interlobular arteries into afferent arteriole, giving rise to glomeruli then efferent arteriole gives rise to PERITUBALAR capillaries.

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22
Q

what occurs with peritubular capilliaries?

A

Peritubular capillaries wrap around arterioles
They have a distinctive shape, called Vasa recta.
Vasa recta is a special type of peritubular capillary (long) wrapped around loop of Henle

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23
Q

What is filtration in kidney

A

Filtration- the movement of fluid from glomerulus capillary into Bowman’s capsule.

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24
Q

What is excretion?

A

Excretion= sum of filtration - reabsorption + secretion.

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25
Q

What is reabsorbtion in the nephron?

A

Reabsorption in nephron: the movement of fluid from the Nephron tubule into peritubular capillary.

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26
Q

What is secretion in the nephron?

A

Secretion: Movement of fluid from peritubular capillary into NEPHRON.

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27
Q

What is secretion in the nephron?

A

Secretion: Movement of fluid from peritubular capillary into NEPHRON tubule

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28
Q

What is the glomerulus filtration rate?

A

Glomerular Filtration rate- rate at which blood is filtered through the glomerulus.
Glomerular filtration- the Bulk flow of fluid from glomerular capillaries into Bowman’s capsule

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29
Q

What is glomerular filtrate?

A

The glomerular filtrate- fluid within Bowman’s capsule (after fluid is filtered), and Does NOT contain cells, essentially Protein-free and contains most INORGANIC ions(Na+ K+, Cl-) and low molecular weight for organic ions.
It is NOT filtered.

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30
Q

What happens during filtration in kidney?

A

during filtration, Fluid moves across glomerular capillary endothelial cell, goes across glomerular basement membrane and moves between podocytes (slit-diagraphsm.
fenestrate- window in glomerular capillary between endothelial layer

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31
Q

What is the order that filtered substances go through?

A

Filtered substances go through:

  1. Fenestrae in glomerular-capillary endothelial layer
  2. Basement membrane
  3. Slit diaphragms between podocyte foot processes.
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32
Q

What is the role of proteins in slit-diaphragm?

A

slit diaphragm: you have PROTEINS that control the GAP between the podocytes

33
Q

What physical aspects (of filtrate) regulate filtration of substances?

A
  1. Substances Size > 70,000 Daltons (or 70 kD) are NOT FILTERED
  2. Electrical charge: negatively charged molecules are LESS filtered due to surface of filtration barriers being coated with polyanions (repel negative charges)
    small molecules you hav
34
Q

Compare and contrast how size of molecules as well as charged molecules may lead to reduction in permeability.

A

Small molecules are able to undergo LOTS of filtration until reach 70 kDaltons (molecules get bigger) , then you start to see a reduction in permeability.
If the molecules are also negative charged (along with > size) , steeper reduction in permeability.

35
Q

What is the journey of fluid from in the nephron?

A

Fluid will move from afferent arteriole into the glomerulus to bowman’s capsule into proximal tubule. Fluid in proximal convoluted tubule will then move into Thin descending loop of Henle, into thin ascending loop of Henle and Then Thick ascending loop of Henle to straight part of proximal tubule in to Distal convoluted tubule which goes to Collecting tubule (cortical) and medullary collecting tubule

36
Q

What structures of renal system are part of Cortex vs Medulla?

A 
In the cortex:
-afferent and efferent arteriole
-macula densa
-glomerulus
-Bowman's capsule,
proximal convoluted tubule and distal convoluted tubule
Cortical collecting tubule
in Medulla: Thin ascending and descending limbs of loop of Henle, Thick ascending limb of Loop of Henle nd Medullary collecting tubule.
37
Q

What are the physical aspects of glomerulus-endothelial cell barrier?

A

Physical aspects of glomerulus-endothelial cell barrier:
Permeability
1. Size of Space/fenestra between endothelial cells.
the Bigger the windows between endothelial cells, the GREATER the permeability (more permeable glomerulus is to substance)
2. Size of Spaces between epithelial Podocytes of Bowman’s capsule
- The size of slit diaphragm determines how easily molecules are filtered

38
Q

What is the GFR? What is the normal level of GFR?

A

GFR= Glomerular Filtration Rate: The Volume of filtrate formed unit time
Normal GFR is Approximately 180L/day
This describes kidney filtering 125 mL/min (a lot of volume)

39
Q

What are the DIRECT determinants of GFR?

A

Direct Determinants of GFR:
Rate of filtration= permeability x surface area x Net Filtration pressure (NFP)
kf= permeability x surface area
GFR= Kf x Net Filtration pressure (NFP)

40
Q

What happens if kidney does not reabsorb a certain amount of fluid?

A

If kidneys do not reabsorb fluid (125mL/min), the fluid will go to the bladder and you will be peeing a lot. kidneys must work to both reabsorb a lot of fluid and pee (get rid of toxins)

41
Q

Describe the role of Kf in filtration? What are its compoments?

A

Kf= Ultrafiltation coefficient; kf= (permeability x surface area of glomerular capillaries)
-Permeability is determined by:
1 Size of space/Fenestra between endothelial cells
2. Size of pores between epithelial podocytes of Bowman’s capsule
-Surface Area- determined by MESANGIAL CELL STATUS and number of viable nephrons.

42
Q

What occurs to the nephrons as you age? What other conditions can cause nephron amount to change

A

As you age, you start to LOSE NEPHRONS
High blood pressure- lose nephrons
Diabetes- lose nephrons

43
Q

What are mesangial cells? How do they relate to podocytes? What occurs if mesangial cells contract vs relax?

A

Mesangial cells- located in middle core of Bowman’s capsule
mesangial cells have interrelationship with podocytes
if mesangial cells relax, Surface area INCREASES, and Kf INCREASES
if mesangial cells Contract, the surface area DECREASES,
Kf DECREASE, which DECREASES GFR

44
Q

What is Net filtration pressure and what are its components?

A

Net filtration pressure: (hydrostatic pressure of glomerular capillary + oncotic pressure of bowman’s capsule) - (hydrostatic pressure of Bowman’s capsule + oncotic pressure of glomerular capillary)
NFP= (P gc + pi BC)= (P bc + pi GC)
The oncotic pressure of bowman’s capsule is NEGLIGIBLE (ZERO).
-since proteins are not filtered, so oncotic BC= 0.

45
Q

What is overall equation for GFR, including the pressures?

A

GFR= kf x NFP (P gc -P bc - pi GC)

46
Q

Describe what occurs with the pressures that determine Net filtration pressure. Are they constant, or do they change? How does this affect NFP (net filtration pressure) ?

A

hydrostatic pressure of Bowman’s capsule (constnt)- 15 mmHg
hydrostatic pressure of Glomerular capillary -60 mmHg
Oncotic pressure of Glomerular capillary CHANGES along capillary because you are reabsorbing fluid that has no protein. (protein concentrated in GC)
Hence Net filtration pressure changes along the Glomerular capillary.
NFP can NEVER be Zero in humans.

47
Q

What factors influence direct determinants of GFR (Kf, NFP (P gc, P bc, oncotic GC) ?

A

1.if Kf increases, then surface area INCREASES (mesangial cells are RELAXED). SA increases, GFR INCREASES
2.Hydrostatic pressure of Glomerular Capillary:
P gc increases if Increase in Renal Arterial pressure
-if AFFERENT arteriole resistance (DILATED), you have Less resistance, P gc Increases
if Afferent arteriole is constricted, GC hydrostatic pressure decreases.
-Efferent arteriole is CONSTRICTED, GC hydrostatic pressure INCREASES and GFR increases
3. Hydrostatic pressure of Bowman’s Capillary:
-this pressure only changes due to pathological problem
-Obstruction of Urinary system (Ureter): push pressure back into renal pelvis to major calyx to minor calyx to renal medulla to nephrons to cortex
So if ureter or urethra obstructed, back pressure to kidneys, so Hydrostatic pressure of BC is REDUCED, REDUCING GFR
4. Oncotic pressure of Glomerular Capillary
-systemic plasma of Oncotic pressure in body increased, GC oncotic pressure INCREASED, GFR DECREASE
- RENAL plasma flow DECREASED, GC oncotic pressure INCREASE (concentrate proteins in GC easier, less fluid) NFP reduced, which DECREASES GFR.
-This happens all the time (renal plasma flow decrese, GC oncotic increase)

48
Q

Describe the properties of Renal Blood FLow? What determines RBF? What is the equation?

A 
Renal Blood Flow:
1.1 L/ min
-20-25% of total cardiac output
-RBF determined by 
-mean arterial pressure
-contractile state of renal arterioles
Renal Blood Flow= Renal Arterial pressure- Renal venous pressure/ R (resistance) 
F= Flow, Change in pressure= pressure difference between arterial and venous vessels; R - resistance
49
Q

What happens to Renal blood flow, if there is an increase in resistance?

A

if resistance goes up, renal Blood Flow will Decrease
The change in resistance produces the same effect on RBF regardless of whether it occurs in afferent or efferent arteriole.

50
Q

Distinguish what happens when afferent and efferent arterioles are constricted and how that affects hydrostatic and oncotic pressures. How does this alter Renal blood flow?

A

If you constrict the Afferent arteriole, Both GFR and Renal Blood Flow DECREASE, since GC hydrostatic pressure decreases.
if you constrict the Efferent arteriole, Glomerular capillary Hydrostatic pressure Increases, which allows GFR to Increase and Renal Blood flow still DECREASES
RBF still decreases because The change in resistance produces the same effect on RBF regardless of whether it occurs in afferent or efferent arteriole
*any CONSTRICTION in afferent or efferent arteriole, you are still INCREASING Resistance, hence DECREASE RBF (renal blood flow)

51
Q

What regulates Renal Blood flow?

A

Regulation of Renal Blood flow:

1) mean arterial pressure
- increase mean arterial pressure, you increase flow
2. Contractile state of of renal arterioles

52
Q

What regulates Renal Blood flow?

A

Regulation of Renal Blood flow:

1) mean arterial pressure
- increase mean arterial pressure, you increase flow
2. Contractile state of of renal arterioles
- more constriction, resistance increases, and RBF Decreases
- a given change in arteriolar resistance produces the same effect on RBF regardless of whether it occurs in afferent vs efferent.

53
Q

What are the functions of Renal Blood flow?

A

Functions of Renal Blood Flow

1) INDIRECTLY determines GFR (hydrostatic pressure, etc)
- decrease in RBF, GC P increases, GFR decreases
2. Modifies rate of solute and water reabsorption by proximal tubule
3) Participates in Concentration (and dilution) of urine
4) Delivers O2, nutrients, and hormones to nephron cells; returns CO2 and reabsorbed fluid and solutes to circulation
5) delivers substrates for excretion in urine
- more RBF takes blood to Glomerular capillaries, filtration takes place, excrete all toxins.

54
Q

What is the only pressure that you can regulates that is also a determinant of GFR

A

Hydrostatic pressure of Glomerular capillary is REGULATED (regulated by regulating afferent, efferent arteriole caliber)
oncotic pressure is not regulated and constantly changes.

55
Q

What is the afferent/efferent arteriole caliber? What regulates the arteriole caliber?

A

Describes how much afferent/efferent are constricted
This caliber regulates hydrostatic pressure of GC
The arteriole caliber is regulated by nerves and hormones

56
Q

How is GFR regulated?

A 
Regulation of GFR:
by Factors that influence afferent and efferent arteriolar caliber (arteriole constriction)
- Renal Sympathetic nerves
-Renin-Angiotensin system
-Autoregulation
-Prostaglandins.
57
Q

How do you regulate the kidneys? Which other body organ has same regulation?

A

Kidney regulated by Nerves, hormones and autoregulation

same regulation occurs in the HEART

58
Q

Why is regulating GFR important?

A

Regulating GFR, regulates the amount of fluid going into nephron tubules which helps regulate:
-amount of fluid being excreted/reabsorbed
-Clearance of Specific molecules (ex: toxins, drugs, certain metabolites)
These functions help CONTROL fluid Volume and Composition.

59
Q

What is the role of Renal sympathetic nerves? How does this affect GFR

A

The Renal Sympathetic nerves control the amount of Constriction of afferent and efferent arteriole
INCREASE Sympathetic nervous activity, DECREASE GFR and decrease RBF Always
Increase in activity of renal sympathetic nerves, you have Constriction of afferent/efferent, which decreases Renal Blood flow and Increase of Oncotic Pressure of Glomerular capillary. The increased Avg oncotic pressure GC will decreases Net Filtration Pressure and GFR Decreases (decreased filtration)
At the same time, constrict both afferent/efferent arteriole, Hydrostatic pressure of GC has small increase initally. As fluid is being filtered out of GC, the hydrostatic pressure of GC decreases, leading to larger decrease in GFR.

60
Q

What is the role of renin-angiotensin system? What are the components and how are they produced.

A

Renin-angiotensin system
Renin (enzyme catalyst) is produced by JG Cells (Juxtaglomerular) that converts angiotensinogen (liver) to Angiotensin I (10 aa)
Angiotensin I is converted to Angiotensin II by action of ACE (Angiotensin Converting Enzyme).
Levels of Angiotensin II dependent on levels RENIN

61
Q

What converts angiotensinogen to Ang I?

A

RENIN

62
Q

What happens to Angiotensin II if more renin is produced?

A

More Renin produced, the more Angiotensin II can be produced.

63
Q

What is structure and function of Angiotensin II?

A

Angiotensin II- small peptide, 8 amino acids long
-Ang II constricts both efferent and afferent arterioles, has MORE effect on Efferent arterioles. This constriction increases P GC (hydrostatic pressure)
Ang II always causes Decrease in RBF, (reduction of RBF causes decease in P gc) but since it has more effect on efferent arteriole, it increases in Hydrostatic pressure of GC (pressures cancel out)
Ang II also Decreases Kf by acting on mesangial cells.
Main point: ANG II Decreases GFR in normal situations.

64
Q

Compare and contrast how Ang II affects GFR in normal conditions vs pathological conditions.

A

Normal conditions: Ang II Decreases GFR
Pathological conditions like Renal Arteriole Stenosis:
-Selective constriction of Efferent arterioles, which helps maintain GFR, so overall reduction is Not severe
It is important Ang II > effect on RBF than GFR.

65
Q

What major factors control Renin secretion?

A 
Control of renin secretion:
controlled by 4 major factors:
1.* Intrarenal baroreceptors
2.* Macula densa
3. *Renal sympathetic nerves
4. Ang II
66
Q

What factors are affected when someone experiences a hemorrhage?

A

If a person has Hemmorrhage (loss of blood, Cardiac output decreases), Arterial pressure will Decrease and extrarenal Baroreceptors ( Carotid artery) will Increase activity of Sympathetic nerves. Increase activity of sympathetic nerves will have direct stimulation of Granular cells (JG cells) which increases Renin secretion. Increase renin secretion, increases Angiotensin II production. Angiotensin II- powerful vasoconstrictor that will help increase Arterial pressure.
Increase in sympathetic nerves, Decreases GFR, which decreases filtration rate and Fluid delivery to macula densa is decreased.
*Decrease fluid delivery to macula densa increases renin secretion

67
Q

What happens to macula densa when GFR is decreased?

A

When GFR decreased, the amount of fluid going to macula densa is DECREASED

68
Q

What happens to renin when fluid delivery to macula densa is decreased?

A

Decreased Fluid delivery to macula densa- INCREASES Renin secretion.

69
Q

What happens when arterial pressure is decreased (corrsponding to perfuson pressure)

A

Decreased arterial pressure decreases renal perfusion pressure (blood flow) which Decreases GFR, decrease filtration, decreasing rate of fluid delivery to macula densa, increasing renin secretion, increase arterial pressure,

70
Q

What happens to arterial pressure (correspond to intrarenal receptors)?

A

Decreased arterial pressure will decrease stretch of granular cells (intrarenal receptors), increasing renal secretion, increase Ang II (vasoconstrictor) and increases arterial pressure

71
Q

Describe what components are part of autoregulation of renal blood flow and GFR.

A

Autoregulation of Renal blood flow and GFR based on:

  1. Myogenic response- similar to ne found in vascular smooth muscle beds
  2. Tubuloglomerular feedback
72
Q

What occurs in autoregulation of kidney?

A

Autoregulation in kidney: mechanism by which the kidneys regulate both Renal blood flow and GFR in the face of changes in blood pressure.
Autoregulation is a fine tuning of kidney due to changes in blood pressure

73
Q

What occurs during Tubuloglomerular feedback?

A

Tubuloglomerular feedback: minute to minute regulation of GFR and RBF in face of changes of blood pressure.
mechanism occurs without nerves and hormones.
Increase in arterial pressure, increase glomerular blood flow, increasing GFR, and increase in Na+/Cl- delivery of fluid to macula densa which causes release of substance (ADENOSINE) that acts on smooth muscle of afferent arteriole, constricting afferent arteriole, Decreasing GC hydrostatic pressure, Glomerular capillary blood flow goes down, and maintain GFR.

74
Q

What kind of structure is adenosine in kidneys?

A

Adenosine is a CONSTRICTOR in the kidneys

75
Q

What initiates the negative feed mechanism for tubuloglomerular feedback?

A

The Na+Cl- delivery to macula densa will intiate negative feedback and cause release of substance (adenosine) that constricts afferent arteriole , leading to decrease RBF and and maintain GFR.

76
Q

What is the role of prostaglandins that regulate GFR?

A

Prostaglandins are local metabolites (fatty acids, 20 carbons) of arachadonic acid produced by both renal sympathetic stimulation and Ang II
2 major prostaglandins produced in endothelial cells of renal arterioles are PGI2 (prostacyclin) and PGE2.
Both of these substances are VASODILATORY which are important to prevent Excessive vasoconstriction during Cardiovascular Stress.
Increase sympathetic nervous activity, significant constriction of arterioles; but to make sure there is not excessive constriction, prostaglandins produced which counteract constriction of arterioles
Also when Ang II acts on kidney, prostaglandins counteract possible excessive constriction

77
Q

What is the role of Nitric Oxide (NO)?

A

Nitric oxide- (labile gas produced by endothelial cells) important VASODILATOR in control of Renal blood flow
(vascular smooth muscle dilates blood vessel)
Nitric oxide counteracts Ang II and Catecholamines (NE, Epinephrine).
When blood flow increases, a greater shear force acts on endothelial cells and increases production of NO.

78
Q

What is dopamine’s role in GFR system?

A

Dopamine- VASODILATOR produced by proximal tubule. Dopamine Increases renal Blood flow inhibit renin secretion.

79
Q

What are the local metabolites in the renal system and what is their funcition.

A

The local metabolites: Prostaglandin, Nitric oxide and dopamine
These metabolites allow for fine tuning of hemodynamics of kidney (restrict constriction)

Systems Physiology (19 decks)

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