RENAL PHYSIOLOGY 4 Flashcards
proximal tubule
major reabsorptive area because of presence of ___, its basolateral membrane are ________ and it has abundant mitochondria
brush borders
invaginated
transport processes
limitation is equilibrium and important factor: permeability and gradient
passive transport
transport processes
includes primary, secondary, and endocytosis
active transport
site of glucose reabsorption
early portion of the proximal of tubule
glucose is freely ______ and ______ reabsorbed
freely
100% reabsorbed
glucose
this is a secondary active transport mechanism co-transported with sodium - utilizing a carrier known as ______________
sodium glucose transporter 2
glucose
across the basolateral when it goes to the blood, it is already done by facilitated diffusion which is _____________
glucose transporter 2
Normal glucose concentration in blood (FBS) is _________
80-110 mg/dL
site of reabsorption of amino acids
early portion of the proximal tubule
amino acids
in the apical membrane is co transported with ____
in the basolateral membrane there is ______/_______ diffusion
sodium
simple or facilitated diffusion
proteins
reabsorption rate
the site is ____________
early portion of the proximal tubule
proteins
they are large, cannot pass through they will undergo ___________ in the apical membrane
in the basolateral membrane they will undergo ____________
endocytosis in the apical
exocytosis in the basolateral
in endocytosis of proteins there are multiligand endocytic receptors
they can bind a wide range of peptides and proteins and thereby mediate their endocytosis:
M
C
megalin
cubilin
reabsorption site of urea
mainly in the medullary collecting duct
Urea us reabsorbed back at the collecting duct through the ________ and it is enhanced by the ________
Urea transporter A1
enhanced by ADH
urea is the waste product of the __________
protein metabolism
uric acid is primarily reabsorbed at the ___________
proximal tubule
uric acid the waste product of ________________-
nucleic acid metabolism
creatinineL excretion rate is ________ to filtration rate
equal
ascorbic acid:
excretion rate is regulated by:
_________ filtration
Tubular reabsorption: _________
tubular secretion: ___________
glomerular filtration
proximal tubule
distal tubule
ascorbic acid tubular secretion
is secreted in the distal tubule promoted by _______– and increased filtered load of ________
adrenal steroid
increased filtered load of sodium
ascorbic acid is primarily absorbed at ________ co-transported with _________
PCT
sodium
is there any substance that is freely filtered, never reabsorbed but secreted? so excretion rate > secretion rate
yes, para-aminohippuric acid and hydrogen
how are organic anions secreted?
from the blood, they can thus diffuse from there to the cell or they are in exchange with ______ utilizing a transported organic acid transporter (____, _____, and ____)
alpha ketoglutarate
organic acid transporter (OAT1, OAT2, OAT3)
how will OA go out from the apical membrane
same it will exchange with ________ but the the transporter they will use is _________
or diffuse utilizing ___________ transporter or the _________ proteins
OAT 4
MRP2 transporter or the multidrug resistance proteins
which of the following organic anion transporters is utilized by apical membrane?
OAT 1, OAT 2, OAT 3, OAT 4
which of the following organic anion transporters is utilized by basolateral membrane?
MRP2 transporter and OAT 4
organic cation secretion crosses the _______ tubule
proximal tubule
organic cation enters the cell across the basolateral membrane primarily by _______
Organic cation leaves the cell across the apical membrane in exchange with hydrogen by __________ and ________ which requires ATP
proximal tubule
multidrug and toxin transporters (MATE 1 and MATE2-K) and by multidrug resistance protein which requires ATP
sodium reabsorption sites
proximal tubule
loop of henle
distal tubules
collecting duct
____________ is achieved by changes in water balance
_____________ is primarily by changes in sodium balance
osmoregulation
volume regulation
in the proximal tubule we divide this into two:
the _________ portion and _______ portion
in the early portion:
reabsorption is cotransported with ______ or in exchange with _______
in the late portion:
reabsorption is cotransported with ____ or in exchange with ________
early and late
organic substances or hydrogen
sodium or hydrogen
sodium in the loop of henle
can also be exchnaged with _______- by reabsorption of sodium here is with 2 chloride and 1_________
hydrogen
potassium
sodium in the early distal tubule
cotransported with ________-
the transported used is NCC which stands for _________
blocked by ______
sodium chloride channel
thiazide diuretic
sodium in late distal tubule and collecting duct
when sodium is reabsorbed it is followed by secretion of _____________- and hydrogen
potassium and hydrogen
Bartter syndrome there is a problem in ____________
Sodium Potassium 2Chloride symporter
sodim is very important in fluid balance, it is in fact the major determinant of _____ osmolarity
ECF osmolarity
hormones that influence sodium reabsorption
stimulates sodium reabsorption in the proximal tubule, thick ascending limb, distal tubule and collecting duct
angiotension II
hormones that influence sodium reabsorption
stimulates sodium reabsorption and potassium secretion in distal tubule and collecting duct
increases sodium reabsorption in the thick ascending limb
aldosterone
hormones that influence sodium reabsorption
secreted in the heart and they inhibit sodium chloride reabsorption as well as ADH
atrial natriuretic peptide
hormones that influence sodium reabsorption
stimulates NaCl reabsorption in the proximal tubule, thick ascending, DT, and CD; same with angiotensin II but without potassium secretion
catecholamines
hormones that influence sodium reabsorption
inhibits reabsorption of NaCl in the proximal tubule
dopamine
hormones that influence sodium reabsorption
increases sodium chloride excretion
__________ same effects with ANP and BNP, encoded in the same gene
kidneys release _________ to normalize blood pressure; only produced in the kidneys
urodilatin
hormones that influence sodium reabsorption
same but it can be produced by other organs aside from the kidney it also causes diuresis and naturesis by inhibiting sodium chloride reabsorption
adrenomedullin
potassium
in the proximal tubule reabsorbs potassium by _____
in the thick ascending LOH reabsorb with ______ and ______
in the distal tubule it is reabsorbed in exchange with ________
in exchange with ______ ( in the late distal tubule and collecting duct
active transport
sodium and chlored (NKCC2)
hydrogen
sodium
calcium sites of reabsorption
proximal tubule, thick ascending loop and distal tubule
two important substances that increases calcium reabsorption
vitamin D and PTH
phosphate is controlled primarily by an ____________
overflow mechanism
phosphate is cotransported with ________-
transporter used ____1,2, and 3
sodium phosphate transporter
magnesium is primarily absorbed in the
thick ascending loop of henle
