1. ANATOMY AND PHYSIOLOGY
RENAL SYSTEM
(Genitourinary)
Lori Baker, RN, BSN

2. 2 kidneys - formation
2 ureters
1 urinary bladder passage and holding
1 urethra

3. Functions
Regulates
Volume
Electrolytes
Acid-base balance

4. Upper posterior abdominal cavity
Retroperitoneal
Protection
Diaphragm
Vertebral column
Lower ribs
Adipose tissue
Renal fascia

5. Hilus
Indentation
Renal artery
Renal vein and ureter

6. 1st Tissue portion
Renal cortex (cortex)
Outer
Parts of nephron
Renal corpuscles and convoluted tubules

7. 2nd Tissue portion
Renal medulla (medulla
Inner
Parts of nephron
Loops of Henle and collecting tubules
Renal pyramids
Tip of each empties urine into other parts

8. Cavity portion
Renal pelvis
Beginning of the ureter
Calyces (calyx)
Funnel-shaped extensions of renal pelvis

9. Review

10. Nephron Structural and Functional unit Millions Where urine is formed
Each has
Renal corpuscle
Renal tubule

11. Nephron Renal corpuscle In renal cortex 2 parts
Glomerulus-capillary network
Bowman’s capsule-encloses the glomerulus

12. Nephron Bowman’s Capsule Inner and outer layer Space between
Renal filtrate – becomes urine
Made from the blood in the glomerulus

13. Nephron Renal Tubule 3 parts Proximal convoluted tubule Loop of Henle
Distal convoluted tubule

14. Nephron Distal convoluted tubules from numerous nephrons empty into
Collecting tubule
Papillary duct
Calyx
Renal pelvis
Peritubular capillaries surround all of these tubules and ducts.

15. Blood Supply In through renal artery Branches off the abdominal aorta
Afferent arterioles
Capillaries of glomeruli
Efferent arterioles
Peritubular capillaries
Veins
Renal vein
IVC

16. Urine Formation Glomerular Filtration
Uses BP – forces things out of glomeruli into Bowman’s capsule
Now renal infiltrate
GFR
Amount of filtrate formed in 1 minute
Depends on blood flow
mL/min

17. Tubular Reabsorption 24 hrs – 150-180 LITERS of renal filtrate
24 hrs – 1-2 LITERS of urine
Most is reabsorbed
Via peritubular capillaries
Proximal convoluted tubi;es

18. Hormones Aldosterone Adrenal cortex Released… If blood K is 
If blood Na is 
If low BP
ANH (atrial natriuretic hormone)
If excretion of Na is , therefore water to increase blood pressure

19. Hormones ADH (antidiuretic hormone)
Released when the body’s water level decreases
Water reabsorbed in distal convoluted tubules and collecting tubules
Only water is affected
PTH (parathyroid hormone)
Increases reabsorption of calcium ions if calcium levels drop

20. Acid-Base balance If body fluids too acidic
More H+ ions into renal filtrate and return more HCO3 ions to blood
If body fluids too alkaline
Return H+ to blood and excrete HCO3 ions in urine

21. Other Kidney Functions
Secretion of renin
Juxtaglomerular cells
Starts renin-angiotensin mechanism to raise blood pressure
Secretion of erythropoietin
Hormone – low blood O2 levels
Stimulates red bone marrow to production of RBCs
Activation of vitamin D
 absorption of calcium and phos

22. Urine Elimination Ureters Peristaltic waves
Bladder compresses ends of ureters when full – prevents backflow
Urinary Bladder
Muscular sac – detrusor muscle
Transitional epithelium
Rugae
Internal and external SPHINCTORS
Urethra

23. Urination Micturition Signal from stretch receptors of detrusor muscle
Spinal cord reflex
Normal – 1-2 L in 24 hrs
Scant = oliguria
None = anuria
Excessive = polyuria
Straw – yellow – from breakdown of bile
pH –