BODY FLUID + ELECTROLYTE BALANCE 2 Flashcards
what are the four key regulator hormones in water output
ADH, aldosterone, antinaturetic pepide, angitensin II
what makes ADH different
the only one that acts on water itself; the other hormones act on salt to act on water
how does ADH maintain blood pressure, blood volume and tissue water content
by controlling the amount of water (urine concentration) excreted by the kidney
why does aldosterone effect blood pressure
because it regulates salt and water in the body
how does ANP regulate salt-water balance and blood pressure
by promoting renal sodium and water excretion and stimulating vasodilation
what makes ANP different
only hormone thats released in response to high blood pressure
how does ANG II raise blood pressure
vasoconstriction, sympathetic nervous stimulation, increased aldosterone biosynthesis and renal actions
increased ECF osmolarity + increased NA concentration in plasma stimulates osmoreceptors in hypothalamus. what does this result in
the posterior pitaurty releasing renin which causes the kidney tubules to absorb more water which decreases urine volume and ECF osmolarity and increases plasma volume
decreased plasma volume and blood pressure inhibit baroreceptors in atria and large vessels. what does this result in
the posterior pitaurty releasing renin which causes the kidney tubules to absorb more water which decreases urine volume and ECF osmolarity and increases plasma volume
what are some causes of dehydration
hemorrhage, severe burns, prolonged vomiting/diarrhea, profuse sweating, diuretic
abuse, water deprivation
what are some signs / symptoms of dehydration
dry mouth, thirst, dry skin, decreased urine output, weight loss, fever,
mental confusion
what causes hypotonic hyperhydration
renal insufficiency or drinking too much too fast
whats the effect of hypotonic hyperhydration
hyponatremia, cell swelling
what are some signs / symptoms of hypotonic hyperhydration
nausea, vomiting, muscle cramps, cerebral edema, disorientation, convulsions, coma, death
what edema
Atypical accumulation of fluid only in interstitial spaces
what does edema result in an increase in
capillary hydrostatic pressure and permeability
whats the effect of edema
impaired tissue function, gas & nutrient exchange
what are some salts
Sodium, potassium, calcium, phosphate
what does salt balance control
fluid movements and balance
what is salt balance essential for
membrane excitability, secretory activity, permeability
what are some examples of salt intake and loss
Intake: foods, fluids
Loss: sweat, feces, urine, vomit
whats the most abundant cation in ecf
sodium
sodium exerts significant osmotic pressure (water follows salt). what does this result in
Plays role in ECF volume and body water distribution
what does sodium content control and why is this important
sodium controls ECF volume which determines blood pressure
what is sodium controlling ECF volume regulated by
RAAS, ANP
what does sodium concentration determine and what is this important for
determines ECF osmolality
Important for neuron and muscle excitability
what is Na concentration controlled by
osmosis, ADH
when is aldosterone released
due to low Na+ or BP
what does aldosterone result in (Na reabsorption + BV)
» ↑ Na+ reabsorption from kidneys
→ Passive ↑ water reabsorption into blood
→ ↑ blood volume
→ ↑ blood pressure
when is atrial neurotic peptide released
due to high Na+ or BP
what does atrial neurotic peptide result in (Na reabsorption + BV)
» ↓ ADH release
→ ↓ Na+ reabsorption from kidneys
→ Passive ↓ water reabsorption into blood → ↓ blood volume
→ ↓ blood pressure
what is ADH (sodium?) released in response to
high [Na+] or low BP
what does ADH result in (Na concentration + BV)
» ↑ water reabsorption from kidneys
→ ↓ urine volume
→ ↓ Na+ concentration
→ ↑ blood volume/pressure
