10. Renal Anatomy and Histology Flashcards
What are the layers of renal fat from proximal to distal to the kidney?
Perinephric fat
Renal fascia
Paranephric fat
What branches does the renal artery give off before reaching a glomerulus?
Renal –> segmental –> interlobar –> arcuate –> interlobular –> afferent arteriole
What nerves supplie the sympathetic innervation to the kidneys?
Lesser and least splanchnic nerves
What supplies the parasympathetic innervation to the kidneys?
Vagus nerve (posterior vegal trunk, right vegus)
What kind of endothelium are found in the ascending and descending portions of long medullary peritubular capillaries?
Ascending: fenstrated endothelium
Descending: continuous endothelium
What are the two main components of a renal corpuscle?
Glomerulus (vessels) and Bowman’s capsule
What kind of endothelium is found in the glomerulus?
Fenestrated endothelium
What is the difference in tissue type between the vascular pole and urinary pole of renal corpuscles?
The vascular pole is endothelium
The urinary (tubular) pole is epithelium
What is the role of mesangial cells?
Provide structural support for glomerular loops and extracellular matrix for podocytes. They are also phagocytic cells and secrete growth factors and cytokines in response to injury.
Where are podocytes found?
Visceral layer of Bowman’s capsule
What is the main role of podocytes?
Form filtration barrier. Regulates size, patency, and selectivity of filtration.
What are the components of the filtration membrane?
Fenstrated endothelium –> basement membrane –> podocytes
What kind of cells make up the parietal layer of Bowman’s capsule?
Simple squamous epithelium
Where is the proximal convoluted tubule (PCT) located? What is its main role?
Only found in renal cortex
Most active tubule in resorption and secretion
What types of epithelium are found in the thin and think limb segments of the loop of Henle?
Thin: simple squamous epithelium
Thick: simple cuboidal epithelium
How can one tell the PCT from the DCT in a histological slide?
PCT: star, jagged shaped
DCT: circular and smoother
Describe the components and role of juxtaglomerular apparatus.
Macula densa monitors Na+ levels and signals juxtaglomerular cells to secrete renin when Na+ is low. Juxtaglomerular cells also secrete renin if they sense BP is low.
What are the two main mechanosensory cell types found in the collecting ducts?
Principal cells (light cells) and intercalated cells (dark cells)
What are the cortical rays seen on a histological slice of a nephron?
Aggregation of collecting ducts and straight tubules running between the renal corpuscles and convoluted tubules
What part of transitional epithelium (urothelium) forms the impermeable barrier on the membrane?
Urothelial plaques. They are stored in fusiform vesicles by umbrella cells until needed.
What cells in transitional epithelium (urothelium) aid in stretching/relaxing of the membrane?
Umbrella cells
What is the name of the muscular sac that encloses the urinary bladder?
Detrusor muscle
Where is the trigone of the urinary bladder located?
Where the ureters and urethra open on the inferior/posterior wall of the bladder
What are the epithelium changes throughout the urethra?
Transitional near bladder
Pseudostratified columnar for majority
Stratified squamous at distal end
What is another name for the penile urethra?
Spongy urethra
What kind of mutation causes polycystic kidney disease?
Autosomal dominant in PKD1 or PKD2
What is schistosoma hematobium?
Parasitic blood flukes passed via snail species. Can cause fibrosis and calcification of bladder
What is nutcracker syndrome?
When the superior mesenteric artery compresses the left renal vein
