Histology Of Urinary System Flashcards
What are the 4 principal components urinary tract
Kidneys
Ureters
Bladder
Urethra
What are the 3 prime layers of the kidneys
Outer cortex - pale
Underlying medulla - darker
Central renal pelvis
What are medullary rays and where are they found
Collection of loops of henle and collecting ducts that originate from the nephrons that have their renal corpuscles in the outer part of the cortex
Renal cortex
What does the renal medulla comprise of
Loops of henle and collecting ducts of nephrons both close to and far from the capsular surface of the kidneys
What is the glomerulus
Tuft of convoluted fenestrated capillaries resting on a glomerular basement membrane
Give the names of the structures that a) line b) support and c) encase the glomerulus
a) podocytes
b) mesangial cells - lie between capillary loops
c) bowmans capsule
How can you distinguish between capillary endothelial cells and mesangial cells histologically
Capillary endothelial cells nuclei lie on the inside of capillaries
Mesangial cells lie between capillaries
What are the 2 components of the juxtaglomerular apparatus
Afferent arteriole
Distal convoluted tubule
How are granule cells formed and whats their function
Endothelium of afferent arteriole expands to form mass of cells - granular cells
These secrete renin in response to low blood pressure
Whats the role of macula densa
Specialised part of the distal convoluted tubule that senses [NaCl] and regulates tubuloglomerular feedback
Where are macula densa found
Closely packed endothelial cells along the distal convoluted tubule
How are proximal convoluted tubule recognised histologically
Simple cuboidal epithelium
Round central/ basal nuclei
Brush border of microvilli at apical end
Many mitochondria - appears eosinohpillic
Function of proximal convoluted tubule
Reabsoprtion of NaCl, proteins, polypeptides, amino acids, glucose
What type of epithelium lines thick and thin segments of the loop of henle
Thick - low cuboidal
Thin - simple squamos
What supplies the loop of henle
Rich vasa recta
How are distal convoluted tubules seen histologically
Low cuboidal epithelium
Scanty microvilli
Numerous mitochondria
Function of the distal convoluted tubule
Regulates acid base by secreting H+ and absorbing HCO3-
Regulates Na level by exchanging Na for K