Renal histology Flashcards
What are the homeostatic functions of the kidneys?
Excretion of metabolic waste and foreign substances through urine
Fluid and electrolyte balance
Metabolic acid-base balance
Production/modification of hormones for BP
Calcium and potassium homeostasis
Production of EPO
What are the parts of the renal corpuscle of the nephron?
Bowman’s capsule
Glomerulus
What are the parts of the nephron’s tubule system?
PCT
Thick descending limb/proximal straight tubule
Loop of Henle with its thin ascending and descending parts
Thick ascending limb
DCT
Collecting duct
What are the layers of the CT capsule covering the kidney?
Outer layer of fibroblasts and collagen
Inner layer of myofibroblasts
What defines a renal lobe?
Single renal pyramid with its overlying cortex
What defines a renal lobule?
In cortex
Single medullary ray and the cortical labyrinth on either side
What parts of the nephron are found in the cortical labyrinth?
Renal corpuscle
PCT
DCT
What parts of the nephron are found in the medullary rays?
Thick descending
Thick ascending
Collecting duct
What parts of the nephron are found in the outer medulla?
Parts of thick descending and thick ascending
Thin ascending and descending
Collecting duct
Loop of Henle of cortical nephrons
What parts of the nephron are found in the inner medulla?
Loop of Henle of juxtamedullary nephrons
Collecting duct
What are the layers of the Bowman capsule?
Parietal - squamous epithelium
Visceral - podocytes
What are histological features of podocytes?
Primary process that embrace capillaries
Secondary foot processes/pedicels connecting the primary processes and bound to GBM with fine filaments
What is the cell adhesion molecule in filtration slit membrane and its function?
Nephrin
Connects actin filaments with adjacent foot processes, which can widen slits
What are the layers of the glomerular basement membrane?
Lamina rara interna
Lamina densa
Lamina rara externa
What is the name given to mesangial cells located outside the renal corpuscle?
Lacis cells
What are the functions of mesangial cells?
Support glomerular capillary loop system
Phagocytosis
Secrete cytokines to repair damage
What protein is secreted by the thick segments of the loop of Henle?
Uromodulin
What is the function of uromodulin?
Role in preventing calcium crystallization
Antipathogenic agent
What thin limp of the loop of Henle is impermeable to water, but permeable to salts?
Thin ascending limb
What water channels are found in the thin descending limb?
Aquaporin 1 channels
What is the epithelium of the DCT?
Cuboidal epithelium with extensive basal and lateral interdigitations
Less-formed microvilli
What are the two types of cells liming the collecting tubules?
Principal light cells
Intercalated dark cells
Where are renin producing cells located?
Juxtaglomerular apparatus, in the walls of the afferent arteriole
Where is the macula densa of distal tubule located?
Juxtaglomerular apparatus
What are the layers of the walls of the excretory passages?
Mucosa - urothelium and lamina propia
Musculosa - inner longitudinal and outer circular
Adventitia - fibroelastic
What are the characteristics of transitional epithelium/urothelium?
Stratified
Large dome shaped cells
Modified apical membrane with plaques and fusiform vesicles to accommodate stretch
What is the additional layer found in the wall of the ureters?
Middle circular layer of smooth muscle
Some serosa in posterior
