renal physiology Flashcards
cortex of kidney
outer portion (but under capsule) houses
parts of the renal tubule and vasculature -glomerular capsule, convoluted tubules (prox and dist), glomerulus, peritubular capillaries, juxtaglomerular complex
capsule of kidney
membranous sheath on outside of kidney
does not permit expansion during inflammation
medulla of kidney
inner portion
May be arranged in masses that are pyramidal in shape.
contains medullary loop and vessels
-nephric loop, collecting ducts, vasa rects
bovine kidney
lobated, no renal pelvis
renal lobe
each pyramid with its cortex
**ADD PIC
papilla of kidney
at the apex of the pyramid at the renal sinus
kidney development
dogs, horses, sheep fuse the pyramids to form medullary mass
bovine kidneys retain multilobar shape
renal pelvis
expansion of the ureter, where all the papillary ducts open into
ureter path
ureter goes from renal pelvis to the dorsal surface of bladder and empties near the neck
renal tubule segments
glomerular (Bowmans) capsule
proximal (convoluted) tubule
nephric loop (loop of Henle)
distal (convoluted) tubule
collecting duct
glomerulus
complex tangle of capillaries in glomerular capsule
keeps cells & large molecules in vessel while filtering out water, electrolytes (glomerular filtrate)
what is the functional unit of the kidney?
nephron
Glomerular filtration rate
rate of filtration through the glomerulus
in beagle- can produce 37ml/14gal of filtrate- must recover some of this!
flow of blood through kidney
- Renal blood flow from the renal artery enters the network of capillaries.
- The afferent arteriole leads into the glomerulus.
- Once through the glomerulus, the capillaries anastomose to form the efferent arteriole.
- The filtered blood flows away from the kidney in the efferent arteriole and eventually leaves the kidney with the renal vein.
2 general groups of glomeruli
- those in the mid and upper cortex
- those near the corticomedullary junction
vasa recta
straight vessels
highly permeable to solutes and water
flow dependent
provide O2 and nutrients to nephron itself
Renal corpuscle
collective term for glomerulus and urinary capsule
urinary capsule vs corpuscle
proximal convoluted tubule
function: absorption
initial mass of recovery of filtered stuff we want to keep (solutes and water)
secrete things we don’t want to keep
thick vs think segments of tubules
variably permeable to water and solute
able to dilute tubular fluid and concentrate salts in the medulla
sets up ability to excrete either concentrated or dilute urine as needed
distal convoluted tubule
dumps into collecting duct
macula densa
part of distal convoluted tubule next to glomerulus
- a specialized segment of the distal convoluted tubule adjacent to companion glomerulus – part of the juxtaglomerular
- Sensitive to the concentration of NaCl in the blood and play an important role in blood pressure regulation
juxtaglomerular apparatus
tubular part: macula densa of distal tubule
arteriolar part: juxtaglomerular cells and afferent arteriole
mesangial cells
juxtaglomerular cells
of afferent arteriole
mesangial cells
dispersed amoung glomerular tuft as well as afferent and efferent arterioles
cortical function
make, then modify filtrate:
- filter
- add/recover substances to/from filtrate
- Peritubular capillary network – deliver materials to and recover materials from tubules
-BP regulation
medullary function
- dilution of tubular fluid
- concentrate medullary salts
- final control over excretion of concentrated or dilute urine
- acid-base balance
- final determination of K+ homeostasis
hormones produced by the kidney
renin: BP regulation
1,25 dihydroxycholecalcipherol: vit D metabolism/absorption
erythropoietin: RBC production
protaglandins: locally vasoactive
renin
produced by kidney
BP regulation
1,25 DIHYDROXYCHOLECALCIFEROL
vit D metabolism/absorption
produced by kidney
erythropoietin
produced by kidney
RBC production
prostoglandins
produced by kidney
locally vasoactive
hormones produced elseware acting on kidney
(know the ones made by the kindey more)!
Antidiuretic hormone – allows urine concentration
Aldosterone – raises systemic blood pressure
Atrial natriuretic peptide – decreases blood pressure
Parathyroid hormone – calcium metabolism
