LECTURE 35 12/5/22 (LECTURE 18 SLIDES: RENAL PHYSIOLOGY CONT.) Flashcards
How long after ingesting 1L of pure water will you expect a change in blood osmolarity?
What will happen with ADH?
What will urine flow rate be after 30 minutes of ingesting 1L of water?
15 minutes (11:00)
Decrease amount of ADH.
6 ml/min at the 30 minute mark
(9:20)
What is a normal ECF fluid volume?
What would the ECF fluid volume be for someone on Diuretic therapy?
14L (Normal)
13L (Diuretic Therapy)
(15:39)
What drug is an osmotic diuretic?
Mannitol - will pull H2O into the nephrons.
Does mannitol get filtered?
Does mannitol get reabsorbed?
Yes, mannitol gets filtered
No, mannitol does not get reabsorbed.
What substance can also act like mannitol?
Glucose that is not reabsorbed will act like mannitol and pull H2O into the nephrons. (18:00)
What enzyme does Acetazolamide inhibit?
What will happen when this enzyme is inhibited?
Carbonic Anhydrase
Carbonic anhydrase contributes to HCO3- reabsorption. If this enzyme is inhibited there would be a decrease in bicarb reabsorption.
If Acetazolamide decreases bicarb reabsorption at the proximal tubule what will happen to H+ secretion?
What does that mean with Na+ reabsorption in the PCT?
What will happen to our urinary output?
Less bicarb reabsorption will mean there will be less H+ secretion.
NHE is slowed down
Decrease in Na+ reabsorption.
NHE is slowed down
Increase urinary output.
(20:00)
Beside using Acetazolamide as a diuretic and antihypertensive, what did Dr. Schmidt mention this drug can be used to treat?
Glaucoma
(21:00)
What transporter will loop diuretics inhibit?
Where is the transporter located?
NKCC Transporter
Thick Ascending Limb of the LOH
What will loop diuretics do to the concentration of the renal interstitium?
Decrease the osmolarity of the renal interstitium.
What transporter will Hydrochlorothiazide act on?
What transporter will Triamterene act on?
Why will these two be given together?
Inhibit Na+/Cl- transporter in the DCT.
Na+ Channel Blocker in the principal cells of the late distal tubule/collecting ducts.
Hydrochlorothiazide is a K+ wasting diuretic and Triamterene is a K+ sparring diuretic. The two drugs given together will mitigate the loss of potassium in the urine.
(25:00)
Calcium channel blockers and NO Donors will __________ the afferent arterioles and _________ hydrostatic pressure of the glomerular capillaries which will __________ GFR.
Relax
Increase
Increase
(26:00)
What kind of receptors will the sympathetic nervous system stimulate on the kidneys?
Beta adrenergic receptors (28:40)
What will happen if there is SNS activity to the kidneys?
Constriction of afferent arterioles that will lead to stimulation of Renin release at the juxtaglomerular cells, resulting in more ANG II. There will also be more Aldosterone release.
Action of SNS on beta receptors in the kidney is to conserve fluid.
Administrating what compound will result in a reflexive SNS activity in the kidneys?
Volatile Anesthetics (30:00)
Why isn’t urine output a perfect way to measure kidney health
Urine output isn’t necessarily correlated to good renal perfusion. The constriction of the efferent arteriole can increase GFR and increase urine output, but also decrease renal blood flow/perfusion. (34:00)
What three factors can increase glomerular sclerosis?
- Increase glomerular pressure
- Increase glomerular filtration
- Excess glucose stuck to the glomerular capillary cells will trigger macrophages attack resulting in sclerosis.
(43:00)
What disease is the number one cause of kidney issues?
Diabetes
What are the consequences of diabetes?
Congestive HF
Acetone/Ketones
Filtration Changes
Edema
Thirst changes
Osmolarity changes
Remodeling
Inflammation and Insulin Resistance
Urinary Changes
Metabolic Syndrome: “X”
Hypertension and Hyperkalemia
Renal Failure
$$$
CAFETORIUM HR $$$
(46:00)
What is the method used by the immune system to destroy stuff? This method is also the root cause of inflammation
Oxidative Stress (46:30)
Remodeling of the kidneys are due to __________.
Scarring
Someone with uncontrolled blood glucose will have a(n) __________ filtration rate per nephron.
Increased or Higher
If someone is chronically hyperglycemic, how is their potassium level?
They will have Hyperkalemia
We did not go over the pathophysiology behind this, maybe next semester
(48:16)
What percentage of our normal GFR would be considered renal insufficiency?
Renal Insufficiency 20-50% of normal GFR (25 to 62.5 cc/min)
What percentage of our normal GFR would be considered renal failure?
Renal Failure 5-20% of normal GFR (6.25 to 25 cc/min)
What percentage of our normal GFR would be considered End Stage Renal Disease (ESRD)?
ESRD <5% of normal GFR (less than 6.25 cc/min)
What items will you want to restrict if someone has renal failure?
Na+ restriction
K+ restriction
Protein restriction
Volume restriction
Do not take this group of medication if you have kidney issues.
Why?
NSAIDs
NSAIDs decrease prostaglandin productions, that are important to the renal medulla areas. The blood vessels in those areas are dependent on prostaglandins for vasa recta perfusion. (57:00)
The prostaglandins that determine medullary renal blood flow are _________ derivatives.
COX-2
(58:00)
What are problems that can result from renal failure?
Increase Na+
Increase K+
Increase Phos
Increase Urea/Nitrogenous compounds
Hypervolemia
HTN
Acidosis
Low Ca+
Anemia
(59:19)
As creatinine is going up, GFR is trending _________.
Down
What is normal concentration of creatinine in the blood?
How much creatinine is filtered each minute normally?
The amount of creatinine removed is dependent on ________.
1 mg/dL
1.25 mg/min
GFR
(73:00)
How much creatinine is produced every minute?
How much creatine is filtered every minute?
1.25 mg of creatinine produced every minute
1.25 mg of creatine filtered every minute.
If you lose half your nephrons what will happen to blood creatinine level?
What will be the new creatinine level?
More creatinine is being produced (1.25 mg/min) than creatinine being filtered (0.625 mg/min). Blood creatinine level will increase.
2 mg/dL
If you lose half your nephrons, how do you get excretion rate of creatinine back in balance with production rate of creatinine?
You will have to wait until plasma creatinine concentration is high enough to pack twice the amount of creatinine into half the original space. This way filtration rate of creatine will equal production rate of creatinine. (90:00)
Mannitol
Class of Diuretic:
MOA:
Tubular Site of Action:
Mannitol
Class of Diuretic: Osmotic Diuretic
MOA: Inhibit water/solute reabsorption by increasing osmolarity of tubular fluid
Tubular Site of Action: Mainly Proximal Tubules
Furosemide and Bumetanide
Class of Diuretic:
MOA:
Tubular Site of Action:
Furosemide and Bumetanide
Class of Diuretic: Loop Diuretics
MOA: Inhibit NCKK transporter
Tubular Site of Action: Thick Ascending LOH
Hydrochlorothiazide
Class of Diuretic:
MOA:
Tubular Site of Action:
Hydrochlorothiazide
Class of Diuretic: Thiazides
MOA: Inhibit Na/Cl co-transporter
Tubular Site of Action: Early Distal Tubules
Acetazolamide
Class of Diuretic:
MOA:
Tubular Site of Action:
Acetazolamide
Class of Diuretic: Carbonic Anhydrase Inhibitor
MOA: Inhibit H+ secretion and HCO3- reabsorption, reducing Na+ reabsorption
Tubular Site of Action: Mainly Proximal Tubules
Spironolactone and Eplerenone
Class of Diuretic:
MOA:
Tubular Site of Action:
Spironolactone and Eplerenone
Class of Diuretic: Aldosterone Antagonist
MOA: Decrease Na+ reabsorption, decrease K+ secretion
Tubular Site of Action: Collecting tubules
Triamterene and Amiloride
Class of Diuretic:
MOA:
Tubular Site of Action:
Triamterene and Amiloride
Class of Diuretic: Sodium Channel Blockers
MOA: Decrease Na+ reabsorption, decrease K+ secretion
Tubular Site of Action: Collecting tubules
What fraction of our total body water is the ICF?
What fraction of our total body water is in the ECF?
2/3 (28 Liters)
1/3 (14 Liters)
What components make up the ECF?
How much fluid is in each component of the ECF?
Plasma (3 Liters)
Interstitial Fluid (11 Liters)
What percentage of our body is made up of water?
60%
What would be the fluid shift and plasma osmolarity (300mOsm/L) with the addition of 2 Liters of 0.9% Saline?
A isotonic solution will increase ECF volume by 2 Liters. Blood Plasma will not change.
What would be the fluid shift and plasma osmolarity (300 mOsm/L) with the addition of 1 Liter of 3% Saline?
A hypertonic solution will increase the osmolarity of the system (>300 mOsm/L). There will be volume expansion in the ECF from the addition of the 3% saline and fluid shift from the ICF to ECF. Total ECF volume will increase >1 Liter.
What would be the fluid shift and plasma osmolarity (300 mOsm/L) with the addition of 0.45% Saline?
A hypotonic solution will decrease the osmolarity of the system (<300 mOsm/L). There will be small increase in ECF and an increase in ICF to balance out the blood osmolarity.
Inulin can only be removed via __________ without _________.
Filtration, Reabsorption
How many mEq of sodium (142mEq/L) is filtered in a day?
25,560 mEq/day
How many mEq of potassium (4.2mEq/L) is filtered in a day?
756 mEq/day
Using this chart. Calculate the blood serum level for each substance.
Glucose = 100 mg/ dL
Bicarb = 24 mEq/ L
Sodium = 142 mEq/ L
Chloride = 108 mEq/ L
Potassium = 4.2 mEq/ L
Urea = 26 mg/ dL
Creatinine = 1 mg/ dL
