Renal 5 Flashcards
mass balance
whatever comes in must be excreted if not needed
behavioural mechanisms
play an essential role in fluid and electrolyte balance
H2O and Na+ determine..
ECF volume and osmolarity
K+ balance can cause problems with..
cardiac and muscle function
Ca2+ is involved in…
many processes in the body
H+ and HCO3- determine..
body pH
The lungs lose water and help remove H+ and HCO3- by excreting…
CO2
Maintaining osmolarity in the body is important because…
water can cross most cell membranes freely
renal tubule cells
constantly exposed to hypertonic ECF and produce organic solutes to match their intracellular osmolarity to the ECF
Some cells use changes in cell volume to…
initiate cellular response
Fluid and electrolyte balance involves…
respiratory, cardiovascular, and renal systems as wells behavioural responses
____________ and __________ are under neural control and are RAPID
cardio, resp
________ responses occur more slowly because it is primarily under endocrine and neuroendocrine control.
Renal
Of the 50-60% water in our body, 2/3 is __________ and 1/3 is ___________.
ICF, ECF
Of the ECF, 25% is _______ 75% is _________.
plasma, interstitial fluid
The conc. or osmolarity of urine is a measure of..
how much water is excreted by the kidneys
diuresis
removal of excess urine
The kidneys control urine conc. by…
varying the amounts of water and Na+ reabsorbed in the distal nephron
vasopressin
controls water reabsorption
With maximal vasopressin…
the collecting duct is freely permeable to water. water leaves by osmosis and is carried away leaving urine CONCENTRATED.
In absence of vasopressin
the collecting duct is impermeable to water and urine is DILUTE
How do the distal tubule and collecting duct alter their permeability to
water?
by adding or removing water pores in the apical membrane under the direction of vasopressin
stimulus of vasopressin secretion?
increased osmolarity
Magnocellular Neurosecretory Cells (MNC)
produce and release vasopressin
vasopressin is aka…
antidiuretic hormone (ADH), AVP
Explain AVP production and secretion..
- osmolarity monitored by osmoreceptor neurons
- increase in osmolarity signals to MNC causing release of AVP vesicles
- AVO released into blood
