Definitions Flashcards
neutral balance
dietary intake plus endogenous production exactly matches excretion
positive balance
intake plus endogenous production > excretion
negative balance
intake plus negative balance
reabsorption
tubules to peritubular capillaries of water and solutes
secretion
peritubular capillaries of solutes only
apical membrane
luminal: urinary space
transport proteins: reabsorption and secretion
villi and microvilli increase SA
tight junctions
basolateral membrane
exposed to interstitium
abundant Na-K ATPase
paracellular transport
through tight junctions between cells
transcellular transport
through cells
claudin 2
protein that makes up tight junctions on luminal membrane
aquaporins
channels to transport H2O when simple diffusion is inadequate
PT and TDLH
proximal nephron
PCT to end of cortical TALH (macula densa)
bulk reabsorption
distal nephron
DCT, connecting tubules, cortical and medullary collecting duct
fine tuning and steep gradients
aquaporin 2
DT
luminal membrane
H20 reabsorption
vasopressin sensitive
aquaporin 4/5
PT (Wall said 3/4 in CD)
baoslateral
H2O to circulation
osmotic pressure
pressure required to prevent osmosis
proportional to [osmotically active particles]
dehydration
loss of water
aquaporin 1
PT
luminal
H20 reabsorption
SGLT1
active: coupoled to Na electrochemical potential gradient
completely reabsorbed until reaches threshold: 200-220 mg/dL
Na/glucose cotransporter
luminal
intestines and kidney
SGLT2
active: coupled to Na electrochemical potential gradient
completely reabsorbed until reaches threshold: 200-220 mg/dL
Na/glucose cotransporter
luminal
kidney
filtrate
similar to plasma without large proteins and cells
more anions due to Gibbs Donnan
myogenic autoregulation
direct stimulation of afferent arteriolar smooth muscle
tubuloglomerular feedback autoregulation
macula densa senses NaCl and alters resistance of afferent arteriole
autoregulation of GFR
- myogenic
- tubuloglomerular
juxtaglomerular apparatus has a role
sweating
hypotonic (half isotonic)
diarrhea
isotonic
HCO3 excretion
vomiting
isotonic
acid excretion
neural stretch receptors
large veins
respond to mechanical stretch
AVP/ADH release; regulates renal Na excretion (NK2Cl channel)
atrial stretch receptors
atria
respond to distention
central signal through vagus
AVP secretion, SNS firing to kidney and CV, ANP secretion
arterial baroreceptors
arteries
respond to increase in BP or PP
AVP secretion
nitrites in urine
bacteria reduce nitrates to nitrites
UTI
bilirubin in urine
liver issues