Renal Physio

Question 1

How does net Hydrostatic pressure change between Efferent & Afferent arteriole? How?

Answer 1

Doesn’t! Stays same due to Eff/Aff via constriction & dilation

Question 2

Formula for filtration/reabsorbtion?

Answer 2

=[(Pgc-Pis)-( πgs- πis)]
=GFR
=Q = Flow

Question 3

What is effective Osmolarity? What forces result?

Answer 3

Osmoles of a substance remain in their respective compartment (impermeable), becoming driving force of Osmotic pressure (osmotic magnet for H2O)- i.e. inulin,

Can be temporary when substances distribute SLOWLY, & have initial osmotic effect (i.e. mannitol, NaCl)

If osmoles freely distribute across compartment, then no Osmotic pressure (urea)

Question 4

Example of loss of isotonic fluid. Draw chart as well.

Answer 4

Hemorrhage (ignore volume from RBCs lost)
Diarrhea
Vomiting
Isotonic pee

Only ECF volume effected (like w/ isotonic gain)