Final Stuff Flashcards
When there is an increase or decrease in blood pressure/blood volume, what happens with ADH?
If blood pressure drops by 5-10%, nothing happens.
more than 20%, ADH rises beyond what is necessary to maintain antidiuresis
if BP rises acutely, ADH secretion is suppressed.
ECF Volume
Sensed?
Sensor?
Effector?
Affected?
Sensed: Effective circulating volume
Arterial and cardiac baroreceptors
Ang II/Aldosterone/SNS/ANP
Urine Na excretion
Plasma osmolality (body water content)
Sensed?
Sensor?
Effector?
Affected?
Plasma Osmolality
Hypothalamic osmoreceptors
ADH
Urine Osmolality (H2O output) + Thirst
Problems with Na balance manifest as what?
Problems with water balance typically manifest as what?
altered extracellular fluid volume
altered plasma osmolality, which is reflected in an alteration in plasma Na+
With GFR, Renin secretion, and Na Reabsorption what happens with SNS?
lowers GFR, increases Renin, and increases Na Reabsorption
What happens to NaCl and water excretion when the ECFV is expanded?
Contracted?
how are these fixed?
expansion –> NaCl and Water excretion are increased when ECFV is expanded
contracte –> expanded.
Fixed by RAAS, SNS, ANP, ADH
What do natriuretic peptides do to GFR, Renin secretion, Aldosterone, NaCl and water reabsorption, ADH?
Increases GFR
Decreases Renin
Decreases Aldosterone
Decreases NaCl and Water reabsorption
Decreases ADH (inhibits it)
What are the 3 things that regulate renin release?
NaCl to the macula densa
SNS
Perfusion Pressure
Salt deficit, what is happening to ADH and RAAS?
Salt excess, what happens to ADH,
Lower ADH to get rid of water, which lowers plasma volume and BP, which signals RAAS
higher ADH which increases plasma volume and blood plasma and ANP raises which lowers RAAS
When do sympathetic nerves increase or decrease activity with volume?
decreased volume = up
increased volume = down
What is the most frequent way that CO2 is transported?
by bicarbonate
Where is bicarbonate reabsorbed?
PCT
TAL
CD
How is bicarbonate reabsorbed in the PCT?
HCO3 Cl antiporter
HCO3 Na symporter
Why have a buffer system anyway?
For secreted H+ regenerates plasma HCO3 that had been consumed elsewhere, it carries this H+ into the urine
Explain how we make NH3?
glutamine helps create NH4, shuffling HCO3 out into the blood and the NH4 into the tubule fluid. this then leaves via NaKCC channels and then comes back into the CD and reforms NH4.
