more renal Flashcards
diabetes insipidus
caused by a failures of the kidneys to respond to ADH. Can be caused by damage to the hypothalamus or pituitary gland as a result of genetic problem
symptoms of diabetes insipidus
a rare condition where you produce large amounts of urine and feel thirsty
diabetes insipidus and diabetes mellitus includes
both type 1 and type 2 diabetes
diabetes mellitus
causes high blood glucose resulting from the boys inability to use blood glucose for energy §
2 cells of collecting duct
intercalated and principle cells
intercalated cells
alpha -H+ and beta- HCO3-
principle cells
ADH works on these cells- inserting aquaproins
what hormone that is related to blood cells is released by the kidneys
erythropoietin
erythropoietin
acts on the bone marrow to stimulate the production of RBC
what powers the reabsorption power of the principle cells
Na/K ATPase pump
what does the Na/K ATPase pump in the principle cells generate
a low intracellular Na+ and a high intracellular K+
how are H+ ions secreted from alpha intercalated cells
Via primary active transport.
Using a lumina H+ ATPase pump- H/K ATPase pump that actively reabsorbs K+ ions whilst secreting H+ ions
how does the H/K ATPase pump of the alpha intercalated cells work
by actively reabsorbingK+ ions whilst secreting H+ ions
ADH secreted from
posterior pituitary
osmolarity of renal medulla: Loop of Henle
PCT: 300 Descending LoH: 400-600-900 Loop: 1,200 Ascending loop: 700--> 400--> 200 Distal: 100
osmolarity of collecting duct
at the top 300 and at the bottom 1200
osmolarity refers to
measure of solute concentration.
osmolarity of the vas recta
descending: 300–> 900
loop: 1,200
ascending: 300 –> 900
what hormone is released by proximal cells
calcitriol
calcitriol
calcitriol is a steroid hormone that has long been known for its important role in regulating body levels of calcium and phosphorus, and in mineralization of bone
vasa recta
blood vessels surrounding the loop of henle
what controls BP
1) myogenic auto regulation
2) tubuloglomerulus feedback
3) neuronal regualtion
which cells are related to tubulglomerulus feedback
macula densa
typical symptoms of diabetes mellitus
glucosuria and polyuria
glucosuria
glucose in urine when not sufficiently reabsorbed
polyuria
excess urine production
- not enough salts being reabsorbed- therefore less water to
- p.pituitary secretes less ADH, therefore little water reabsorbed in collecting duct- decrease in aquaproins
the deeper down the loop of henle..
the more salty
filtrain membrane consists of
1) capillary endothelial fenestrations
2) gel-like basement membrane
3) slit diaphragms within filtration slits between the foot processes of podocytes
whats in the glomerular filtrate
water, glucose, amino acids, urea - like plasma
how much wine do you produce in a typical day?
typically, less than 2L/day - 98-99% of filtrate is reabsorbed
what diseases are likely if the GFR is took high
if too high filtrate passes through the tubules too quickly and cannot be reabsorbed
-diabetes mellitus and diabetes insipidus
a low GFR suggests
chronic renal failure
why is use of creatine less accurate than inline when calculating GFR
due to some being secreted and absorbed in the tubules
why is chronic renal failure deadly
1) waste products accumulate in blood
2) pH and electrolyte balance jeopardised
3) blood volume control impaired (hypertension and oedema)
if the macula dense cells monitor that filtered na+/flow rate increases, GFR is..
decreased
where are essential nutrients like glucose, amino acids and electrolytes reabsorbed
proximal tubule
-rleies on secondary active transport of Na+ (Na+/K+ ATPase pumps)
what secretion takes place in the proximal convoluted tubulues
H+ and organic ions (acid-base balance and waste)
water is reabsorbed… along the descending loop of henle
passively
Na+ is actively reabsorbed along the ..
ascending loop
which cotransporters pump Na+ out of ascending loop
Na+/K+/2Cl-
what powers the Na+/K+/2Cl- co transporter used to reabsorb Na+ in ascending loop
Na+/K+ ATPase pump
descending loop is permeable to
water but not solutes and leaves via osmosis
ascending limb is..
impermeable to water but not to solutes. Na and Cl exit via AT
where does further reabsorption of water take place
the collecting duct- ADH
higher conc of solutes at
both of tubule
diuresis
urine
antidiuresis
less urine
which cells monitor a fall in BP and GFR
juxtaglomerular cells- activate RAAS system
which other cells regulate GFR
macula dense but short term via tubuloglomerular
short term response to dehydration
ADH
long term response to decreased body fluid volume
RAAS
parathyroid hormone
Ca2+ reabsorption
if the K+ conc of the body is reduced by 1/3
paralysis due to nerves being unable to generate AP
if the Ca2+ conc of the body is reduced by half
titanic skeletal muscle contactions
hyponatramia
not enough Na. Cause hypovoleamia, euvolaemia and hypervolaemia.
hypernatramia
too much Na- much rarer. Potent stimulator of thirst
sodium is largely located
extracelullarly
potassium is largely located
intracellular
hypokalaemia
causes diuretics, diarrhoea/vomiting
hyperkalaemia
renal failure, tissue damage, acidosis, aldosterone impairment
clinical changes that hyperkalaemia can bring
ECG changes, Kussmaul breathing (hyperventilation). Depolarisation of excitable cells.
principle cell and K
secrete in exchange with Na+
interrelated cells and K
reabsorb and exchange with H+
which aquaporins in collecting duct and DCT
aquaporins
acidosis results in
depression of CNS
alkalosis results in
over excitability of the CNS and PNS
aldosterone causes the insertion of
Na/K ATPase pumps, so more Na+ is reabsorbed
ANP also inhibits the release of
aldosterone and ADH
