Renal Anatomy & Physiology Review (24)

What are the renal system functions?

Excretion

Selective reabsorption

acid-base balance

blood pressure regulation

endocrine functions

metabolic functions

immune system

What is excretion of the renal system?

Removal of waste and toxins

(urea, creatinine, uric acid, drugs, metabolites)

What is the selective reabsorption of the renal system?

Reclaims nutrients (glucose amino acids)

Regulation of water and electrolyte balance (sodium, potassium, chloride, calcium, phosphate, & magnesium

What is the acid-base balance of the renal system?

reabsorbing bicarbonate and excreting hydrogen ions and ammonium

converts glutamine → bicarbonate

What is the blood pressure regulation of the renal system?

secretes renin in response to hypotension/hyponatremia

• Renin = Angiotensinogen → Angiotensin I

• ACE = Angiotensin I → Angiotensin II

• Angtiotensin II

  • Vasoconstriction

  • Aldosterone secretion

    • Increase sodium reabsorption = increase water retention

    • = increase blood pressure

What are the endocrine functions of the renal system?

-Secrete erythropoietine → red blood cell production

-vitamin D activation to calcitriol → bone homeostasis

What are the metabolic functions of the renal system?

Gluconeogenesis (2nd to the liver)

Amino acid synthesis (arginine, tyrosine, glycine)

Creatinine synthesis (first step)

What are the immune system effects of the renal system?

Antigen sampling/presentation

Inflammatory molecule clearance

What are the 5 main parts of the kidney?

Cortex

Medullary Pyramids

Calyx

Renal Pelvis

Hilum

What are the 2 main components of the Nephron?

Renal Corpuscle

Renal Tubule

What are the components of the Renal Corpuscle?

Glomerular (Bowman’s capsule)

Glomerulus

What are the components of the Renal Tubule?

Proximal convoluted tubule (PCT)

Nephron loop (Loop of Henle)

Distal convoluted tubule (DCT)

What are the components of the Juxtaglomerular apparatus?

Granular juxtaglomerular cells (secrete renin)

Macula densa (sense NaCl in tubular fluid to modify renin secretion)

What are the functions of the Proximal Convoluted Tubule (PCT)?

acid-base balance : HCO3-

Reabsorption of filtered solutes and water (~ 70% of NaCl, Ca+, K+, Mg2+)

Secretion (unfiltered nitrogenous wastes, drug metabolites)

Gluconeogenesis

Vitamin D activation

What are the functions of the proximal tubule?

Active transport

Passive transport

What is absorbed in the Nephron loop?

Filtrate

water

Na+

Cl-

Mg2+

What does the loop of Henle do?

Pulls water of out lumen

What does the DCT do?

Similar to ascending thick limb of LoH, reabsorbs solutes

What happens in the collecting duct?

remaining water and solutes is reabsorbed through hormonal regulation

• antidiuretic hormone

• Aldosterone

What are the two separate cells present in the collecting duct?

Principal cells

Intercalated cells

What are the drugs that work on the nephron?

Thiazide diuretics

Loop Diuretics

SGLT2 inhibitors

Potassium sparing diuretics

Carbonic anhydrase inhibitors

What is the site of action of thiazides?

DCT

What is the site of action of loop diuretics?

Ascending limb of loop of henle

What is the site of action of SGLT2 inhibitors?

PCT

What is the site of action of potassium sparing diuretics?

collecting duct

what is the site of action of carbonic anhydrase inhibitors?

Proximal convoluted tubule

What are the thiazide diuretic drugs?

Hydrochlorothiazide

What are the loop diuretic drugs?

Furosemide

Torsemide

Bumetanide

What are the SGLT2 inhibitor drugs?

Empagliflozin

Dapagliflozin

Canagliflozin

What are the potassium sparing diuretic drugs?

Spironolactone

Eplerenone

What are the carbonic anhydrase inhibitor drugs?

Acetazolamide

What are the drugs that affect the RAAS system?

ACEIs

Angiotensin II receptor blockers

direct renin inhibitors

What are the ace-i drugs?

Lisinopril

Ramipril

Enalapril

What are the Angiotensin II receptor blocker drugs?

Losartan

Irbesartan

Olmesartan

Valsartan

What are the direct renin inhibitor drugs?

Aliskiren