Lecture 21 - Urinary Flashcards
components of the kidney
cortex (renal corpuscles) and medulla (tubules only) which contain the calyces. Covered by a fibrous capsule
Renal corpuscle
golmerulus and capsule filters blood
Proximal tubule
convoluted tubule (65% of reabsorption) and a straight short duct. Enters the outer medulla from the cortex
Loop of Henle
thick descending (15% of reabsorption), thin descending, thin ascending, and thick ascending duct. Occurs in the medulla
Distal tubule
thick ascending duct and thick convoluted tubule. reenters the cortex and has the macula densa.
glomerulus
large bed of capillaries in the corpuscle.
Cell type in the corpuscle and their function
podocytes that aid in the filtration of the blood.
Macula densa
highly compacted cells of the distal convoluted tubule adjacent to the arteriole. can control the flow of blood into the renal corpuscle. by secreting renin to the juxtaglomerular cells.
Parietal layer of the corpuscle
capsule
Visceral component
highly branched arterioles and capillaries that are surrounded by podocytes that aid in the filtration into the urinary space outside the blood vessels and then connected by the proximal convoluted tubule.
Pedicles
branches from podocytes that cover the capillaries. will form the filtration slits
What are cell sin the macula densa sensitive to?
sodium chloride concentration in the distal convoluted tubule. a decrease will cause an increase in blood flow in the afferent arteriole
Mesangial cells
help clean the basement membrane surrounding the capillaries.
Which tubule will have a prominent microvilli brush border?
proximal convoluted tubule and thick descending tubule
Filtration membrane
fluid passes from the capillary lumen through fenestrations across a thick basement membrane and through thin slit diaphragms between pedicles of podocytes and into Bowman’s space
Thin ascending absorption
NaCl but not water
Aldosterone’s role in kidneys
promotes sodium and water reabsorption in the distal convoluted tubule and collecting ducts.
Vasopressin’s role in kidneys
increases permeability of collecting ducts to water which is osmotically pulled from the filtrate.
Vasa recta
bed of capillaries surrounding the loop of Henle.
Peritbular capillaries
capillaries associated with convoluted tubules.
Outer stripe of medulla
Thick and thick
Inner strip of medulla
Thick (ascending) and thin (descending)
Inner zone of medulla
Thin and thin
Collecting duct appearance
intercellular borders. Minimal mitochondria
Ureters epithelium
transitional epithelium or urothelium and surrounded by smooth muscle
Whats a histologically distinct feature of transitional epithelium
binucleated cells
