Na+ and water balance Flashcards
the fact that the ___ has double the volume of the ___ means that the clinical signs of dehydration are muted
ICF>ECF
28L:14L
concn of Na and K+ in ICF and ECF
Na+ = 4mmol/l ICF : 140mmol/l ECF
K+ is the reciprocal
body uses ___ to regulate ECF volume
Na+ concn
if pathology causes Na+ excretion to increasse => ___ Na+ loss exclusively => ___ signs of dehydration that develop ___
ECF
obvious
quickly
Na+ is controlled by _____ activity
= causes Na+ retention in exchange for __+__
mineralocorticoid
K+ and H+
if mineralocorticoid activity is too low then __ is lost => __ lost
Na+
H2O
ADH acts on the __ causing ____
if it has a high level => ___ urine with ___ osmolarity
renal tubules
H2O retention
concentrated urine
high osmolarity
countercurrent multiplication occurs in the ___ and leads to the production of ___ urine
loop of Henle
hypoosmotic urine
Na+ and water balance:
in thick ascending limb in loop of Henle process =
it is ___ to water
active reabsorption of NaCl to the renal medulla
impermeable
Na+ and water balance:
in descending limb of loop of Henle process =
water moves into the medulla
Na+ and water balance:
in thin ascending limb of loop of Henle process =
passive diffusion NaCl to the medulla
the most common cause of a low Na+ concn = low level of ___ this can be caused by __/___
H2O
not drinking enough/ diabetes insipidus
In Addision’s ____ activity is reduced
this causes Na+ to ___ and K+ ___
mineralocorticoid
Na+ low levels
K+ retention
SIADH causes __ to increase and although dont have symptoms of it the basic biochem shows ___
H2O increase
hyponatraemia (because of increased H2O)
an exogenous ADH that can be used in DI
desmopressin
