We discussed in class the effect of constriction of the afferent and efferent arterioles on Renal Plasma Flow (RPF) and Glomerular Flow Rate (GFR). Assuming that GFR can be approximated by GFR = q*RPF*PGC where PGC is the Hydrostatic Pressure in the Glomerulus and q is a conversion factor with units of 1/pressure, derive with equations and show that GFR first increases and then decreases as the resistance of the efferent arteriole Re is increased. (a) To develop the equations, use the electrical model on the right which is analogous to the kidney system of interest. In an electrical analogue, voltages are representative of pressures and currents are representative of flow. (b) Derive an expression for I and another for VGC. Show the final equation for the electrical analogue giving I*VGC which is equal to the analogue of GFR