FInal (Renal System) Flashcards
Functions of Kidneys
filter blood
eliminate wastes
regulate water and ion balance
modulate pH
regulate BP
produce hormones
Properties of Kidneys
0.4% of body weight
recieve 20-25% CO
Cortex
bowman’s capsule
pt
dt
Medulla
loh
ct
Nephron
functional unit of kidneys
Vascular pole
where the afferent and efferent arterioles enter and exit the glomerulus
Urinary pole
where the ultrafiltrate exits the bowman’s space and pct begins
podocytes
highly specialized epithelial cells that wrap around the capillaries at the glomerulus
afferent arteriole
brings in unfiltered blood that becomes waste
efferent arteriole
filtered blood that goes back to the heart
glomerulus
filters blood
peritubular capillaries
filters blood that becomes waste
excretion
afferent arteriole->glomerulus->pct->loh->dt->ct->bladder
reabsorption
afferent arteriole->glomerulus->efferent arteriole->peritubular capillaries->vasa recta->renal vein
reabsorption can also occur in pt (30%), dt, and loh
passive and active transport
filtration
occurs in the glomerulus
occurs first
more filtration than secretion
secretion
pt, dt, ct
loh
used for reabsorption
amount of solute excreted
amount reabsorbed+amount secreted
secretion
more specific
net filtation pressure
total pressure that promotes filtration (BP. colloid pressure)
decreased plasma protein conc.
increased GFR
increased pressure
increased GFR
decreased pressure
decreased GFR
juxtaglomerular apparatus
affect dilation or constriction of vessels to macth filtration rates
membrane transporters
saturation
specificity
competition for binding
urea
a nitrogenous waste product (50% reabs and 50% secret.)
xenobiotics
foreign molecules that arent found in the body
Why is reabsorption favored in the peritubular capillaries
hydrostatic pressure lower in the peritubular capillaries due to farther distance
reabsorbtion occurs in the opp. direction than filtration
creatinine
measures kidney func. (estimates GFR)
GFR
if only filtered, clearance=GFR
inulin
polysaccharide (complex carb. from plants)
100% excreted
glucose
most of it reabsorbed (~100%)
in urine for diabetic patients
SGLT2
diabetic drug
prevents reabsorption of glucose, thus excreted
penicillin
high secretion, so high excretion
low filtration
micturition
process of urination
osmolarity
increases as you go nephron (by the time it gets to the loh)
ALOH
solute reabsorption->hyperosmotic
less heat loss
DLOH
fluid reabsorption->hypoosmotic
heat loss
countercurrent exchange
vasopressin (ADH)
if supressed, more dilute urine
higher at night
peptide hormone
faster response due to aquaporins
BP
decreased BP and BV=water is conserved
increased thirst and water intake
aldosterone
increased k+ conc.
increased BP
steroid hormone
increased na+ reabs.
released by adrenal cortex
angiotension II
peptide hormone
increased BP and CO
triggers vasocontriction
increases vasopressin secretion (increased thirst)
can be reduced by targeting ACE, ARBs, direct renin inhibitors
antihypertensives
diuretics
beta blockers
calcium channel blockers
ANP
decreased myocardial stretch
decreased BV and BP
peptide hormone
increased na+ and H2O excretion
increased GFR by vasodilation
inhibits RAAS
BNP
decreased myocardial stretch
peptide hormone
importatn clinical marker in patients with HF
natriuresis
na+ loss
diuresis
h2o loss
