Exam 3: Kidneys Flashcards
Name the Parts of the Nephron
Renal Corpuscle, Podocytes, Proximal Tubule, Loop of Henle, Distal Convoluted Tubule
Name the 2 Parts of the Renal Corpuscle
Glomerulus and Bowman’s Capsule
What are Podocytes used for?
*Where are they located?
Filtration
*On top of the glomerulus
Name the 4 Parts of the Loop of Henle
Thick/Thin Ascending/Descending Limb
What does the Distal Convoluted Tubule do?
Dumps into collecting ducts/tubule
Where does Filtration Primarily Occur in the Kidney?
Glomerulus moves fluid from the blood to Bowman’s Capsule
*Bowman’s Capsule produces 100% of the filtrate
Where does Reabsorption happen in the Kidneys?
All through the tubules; Mainly Proximal Tubule
Where in the Kidney does secretion happen?
Thru the tubules
What does the Proximal Tubule Reabsorb? 6 things
Glucose, Water, Bicarb, K+, AA, Na+
Where is the Macula Densa Located?
*Function
Located at the end of the Ascending Loop of Henle, touching the Glomerulus
*Monitors Osmolality and volume of fluid in the distal tubule
Where is the JG Apparatus Located?
*Function
At the Vascular Pole of the Renal Corpuscle
*Regulates BP by Synthesizing Renin
What controls the GFR in the Kidneys?
JG Apparatus
How is GFR controlled in the kidneys?
Increase Na+ = Increase BP
Alter Capillary SA
Control Arteriole Diameter
Autoregulation
Neural Regulation [NE and Epi]
Hormonal Regulation
Describe the Function of the Sodium Hydrogen Exchanger (NHE3)
*What does this Exchanger form?
Na+ is pumped into the ISF back to the body and H+ is pumped out into the urine
*H+ binds w HCO3 to form Carbonic Acid H2CO3
What is the end result of the NHE3 Exchanger?
Na+, H2O, and HCO3 are put back into circulation
What Drug/Drug class blocks the NHE3 Exchanger?
Acetazolamide; Carbonic Anhydrase Inhibitors
What are the 5 (6) Major Diuretic Classes?
Carbonic Anhydrase Inhibitors
Loop Diuretics
Thiazides
K+ Sparing
Osmotic
SGLT2 Inhibitors
What is the MOA of Acetazolamide?
*What Drug Class
*What pH imbalance can it cause?
Oldest Class of Diuretics; mostly used for altitude sickness
*Blocks the NHE3 Exchanger, which wastes NaHCO3, K, and Na+
*Can lower pH and cause Metabolic Acidosis, as it has more free floating H+
*Carbonic Anhydrase Inhibitors
What is the MOA of Furosemide?
*Drug Class?
*pH Imbalance
*Toxicity
*Electrolyte SE
Works in the Thick Ascending Limb of the Loop of Henle
*Loop Diuretics
*Increased pH: More likely to develop Alkalosis
*Targets the NKCC2 Transporter [Sodium Potassium 2 transporter] - more Na+ builds up in the lumen, so more Na+ is sent into the urine followed by water
*Allergy is most toxic effect
*Lose Mg and Ca
What is the only Loop Diuretic that is not a sulfa?
Ethacrynic Acid
If a Pt has a sulfa allergy, what diuretic can they not take?
Loop Diuretic, Thiazides
What is the MOA of Hydrochlorothiazide?
*Drug Class
*Synergistic effect when combined with which diuretic class?
*What electrolytes does it lose (little amount)
Targets the NCC co-Transporter (Sodium and Chloride co-transporter) - Inhibits Na+ Transport in the distal convoluted tubule
*Thiazide Diuretics
*Loop + Thiazide
*Bicarb and K
Name 2 K+ Sparing Diuretics?
Spironolactone and Amiloride
MOA of Spironolactone/Amiloride
*Drug class
Antagonize the effects of aldosterone and inhibit Na+ influx in luminal membrane by slowing down the ENAC
What is ENAC in the kidneys?
*What does it do
Epithelial Sodium Channel
*Increases Na+ reabsorption, H2O = Increased BP
Where does Mannitol mainly work?
*Where can it effect in the kidney
*Drug Class
Proximal Convoluted Tubule
*Any water soluble area of the tubule is affected by Mannitol
*Osmotic Diuretics
What is a normal body Osmolality?
300 mOsm/Kg
What are SGLT2 Inhibitors
Glucose Transporters that assist in removing water in the urine
What are indications for K+ Sparing Diuretics?
*Toxicity?
Conn’s Syndrome, CHF, Nephrotic Syndrome, Pit Tumor, Adrenocortical Tumor
*HyperK+
Indications for Mannitol
Increased ICP, hemolysis, radiocontrast agents
Mannitol Toxicity
Renal Failure - Acute Hyponatremia
Dehydration - HyperK and Na+
Diuretics in Pts w DI
Insufficient ADH - excessive urination and thirst
Thiazides - Decrease Plasma Volume = Decrease GFR
Where is aldosterone located?
*Where is it secreted
*How does it increase BP
Collecting Tubule
*Adrenal Cortex
*Increase Na+ and H2O uptake via ENaC
ADH Agonist vs Antagonist
Agonist - Vasopressin
Antagonist - Conivaptan
What is the most common use for a Diuretic
Peripheral or Pulmonary Edema
What is DI
Insufficient ADH = Polyuria and Polydipsia
Tx for DI
Thiazides
*Decrease Plasma volume, GFR
