Intro To Urinary + anatomy Flashcards
(33 cards)
What happens when the ECF ____ is uncontrolled?
a) Volume
b) Osmolarity
a) Changes the BP
b) Shrinks or swells the cell
Why do the kidneys affect the ECF directly and the ICF indirectly?
The kidneys can only affect the ECF by altering water and ion reabsorption, and the ECF affects the ICF
What happens when the ECF is hypertonic or hypotonic? What state does the kidney want to maintain?
Hypertonic ECF: cell shrinks
Hypotonic: fluid flows into cell, cell grows
Want to maintain an isotonic state
What is the ultrafiltrate?
The amount of water and ions that gets filtered (180/L), most is recovered
How much blood flow does the kidney require at rest?
25%
What is the anatomical location of the kidneys?
Retroperitoneal, behind the peritoneum at T11/T12
What nephron structures lie in the Cortex? What’s in the medulla?
Where does the medulla feed into?
Cortex: PCT and DCT
Medulla: Loop of Henle and Collecting duct
The minor-major calyx, hilum, renal pelvis, ureter
What’s the GFR per min and per day?
125 mL/min, 180L/day
What should be absorbed in the PCT?
Why does the filtrate remain isotonic?
Where does reabsorbed material filter through?
100% glucose and amino acids
80-90% K+
60-70% Na+ and water
Remains isotonic because the solute: water ratio remains the same though the volumes of each differ
Peritubular capillaries take reabsorbed material
What makes epithelial cells polarised (in the PCT)?
Discuss the role of the sodium pumps and how it is electrical and osmotic
The luminal membrane (facing the filtrate) has differing properties to the basolateral membrane faces the capillaries
- Na+ enters the cell via ENaC channels across the luminal membrane passively down its concentration gradient
- Energy from Na+ movement drives reabsorption of other substances like glucose and amino acids
- Na/K ATPase continuously pumps Na+ into the ECF so the intracellular Na+ stays low and Na+ can continuously leave the filtrate passively!
Electrical: as the positive Na+ movement attracts Cl- and osmotic because water follows and the PCT wall is permeable to water
What is the main function of the Loop of Henle
To concentrate urine:
Water moves out of LOH as the medullary interstitium is highly concentrated and the descending limb is impermeable to water
What is reabsorbed and secreted in the DCT?
Variable reabsorption of electrolytes and water, H+ is secreted
Which kidney is lower and why?
The right kidney due to the liver
What structure is directly behind the kidneys? Name 3 organs your likely to find immediately anterior to the kidneys?
Diaphragm is posterior
Anterior:
1. Stomach: anterior to the superior left kidney
2. Liver: anterior to the superior right kidney
3. Small intestine anterior to the inferior right kidney
4. Jejunum: anterior to the inferior left kidney
What muscles lie directly behind the kidney going from medial-lateral, what separates these muscles?
Psoas major, Quadratus laborum, transverse abdominis. Separated by thoracolumbar fascia
What structure insulates and protects the kidneys? What structure directly envelopes this?
Perinephric fat, enveloped by renal fascia
What is the pathway of the ureters?
- Superiorly continuous with renal pelvis
- Descend down medial part of psoas major
- Crosses the common/external iliac arteries into pelvis at the ‘pelvic brim’
- Enters bladder obliquely
What is hydronephrosis?
Swelling of the kidney due to buildup of urine - causing a backflow which can damage the calyces and papilla
What are the 3 constriction points along the ureter?
What can occur within these restriction points and what causes these?
- Ureteropelvic Junction: leaving the renal pelvis
- Pelvic inlet: crossing the external iliac artery
- Entrance to bladder
Kidney stones, caused by insoluble substances, can become stuck at any of these points
What causes Nutcracker syndrome?
Since the L renal vein is longer and passes under the superior mesenteric artery it can become entrapped between the SMA and the abdominal aorta
This increases the renal vein pressure which causes inadequate venous drainage
What’s the pathway for renal arteries?
What’s the pathway for the renal veins?
Branch off the abdominal aorta and travel to the cortex: give off renal artery - segmental artery - interlobular artery - arcuate artery (and cortical radiate artery) –> afferent
Renal veins: branch off the aorta and arise inferiorly to SMA draining into the IVC
How does blood travel from afferent - efferent arteriole?
What is a key difference between the glomerular capillaries and the peritubular capillaries?
Afferent arteriole- glomerulus - efferent arteriole- peritubular capillaries - venous system
Glomerular: specialized for filtration, has an increased pressure
Peritubular: specialized for absorption, decreased pressure
What is the trigone?
A triangular region between the 3 openings of the bladder
What is unique to the male pelvis?
Has a connection between the urinary and reproductive tract:
Vas deferens carry sperm from the testicles to simple tubular glands posteroinferior to the blader that store and produce components of sperm (semen)
The ejaculatory ducts carry the semen through the prostate gland and into the urethra - comes out the penis :)
