Lecure 55 - Renal Microanatomy Flashcards
renal capsule
diffuse fibrous covering over the kidney
renal cortex
outer portion of renal parenchyma
renal medulla
inner portion of renal parenchyma
renal pelvis
dilated upper part of the ureters that allow urine to flow from kidney into ureters
calyx
cup the papilla/pyramid and acts as funnel to renal pelvis
hilus
entrance/exit point for renal vessels and exit for ureter
renal pyramid
medulla organized into triangular-shaped pyramids, tips point to renal pelvis
renal papilla
tip of renal pyramid
renal columns
extensions of the cortical tissue that borders the pyramids
cortical labyrinth
regions of the cortex that are composed of the highly coiled and tortuous tubules
medullary ray
regions of the cortex that are composed of the straightened tubules as they are directed to and from the medulla and are centered around a collecting duct
T/F: cow kidneys are multilobar and dogs/cats/horses are unilobar
TRUE
why are cat kidneys tan
lipid retention in tubular epithelium
the functional unit of kidneys is a
nephron
describe the route through the nephron
- glomerulus/Bowman’s capsule
- proximal convoluted tubule
- thick descending limb
- descending limb of henle
- ascending limb of henle
- distal straight tubule
- distal convoluted tubule
- collecting duct
what composes the loop of henle
- thick descending limb (proximal straight)
- thin descending limb
- thin ascending limb
- thick ascending limb (distal straight)
what composes the cortex
- renal corpuscle
- proximal convoluted tubule
- distal convoluted tubule
what composes the medulla
- proximal straight tubule
- distal straight tubule
- thin nephron loop
- collecting duct
where are cortical nephrons found
- outer cortex
- short thin loops
where are juxtamedullary nephrons
- deep cortex
- long thin loops
describe the glomerulus
- tuft of capillaries
- supported by mesangium and mesangial cells
- covered by visceral epithelial cells (podocytes)
- contained in Bowman’s capsule
- lined by parietal epithelium
what 3 things make up the glomerular filtration membrane
- fenestrated capillary endothelium
- glomerular basement membrane
- visceral epithelial cells
what stain highlights the microvilli of the proximal tubule
periodic acid-schiff stain (PAS)
T/F: the epithelial cells of distal convoluted tubules lack microvilli
TRUE
the collecting ducts join to form
papillary ducts
what makes the juxtaglomerular apparatus
- distal straight tubule (macula densa)
- vascular pole of renal corpuscle (afferent arteriole and granular cells)
- extraglomerular mesangial cells
macula densa
cluster of cells that resides immediately adjacent to vascular pole
juxtaglomerular [granular cells] are
modified smooth muscle
what is the main function of the juxtaglomerular apparatus
regulate blood pressure and filtration rate of glomerulus
what is in the interstitium
- loose CT
- fibrocyte and collagen fibers
summarize the flow of blood in the kidney to the capillary bed
- renal a.
- lobar a.
- interlobar a.
- arcuate a.
- interlobar a.
- glomerular capillary bed
summarize the flow of blood in the kidney from the capillary bed
- glomerular capillary bed
- glomerular efferent arteriole
- peritubular capillary plexus
- interlobar v.
- acruate v.
- interlobar v.
- lobar v.
- renal v.
the efferent arterioles branch to
descending and ascending vasa recta
the formation of the descending and ascending vasa recta causes what kind of current
countercurrent exchange
T/F: the inner medulla is the last to receive oxygenated blood
TRUE
