Afferent Arteriole Resistance Formula

Equation for calculate afferent arteriole resistance is,

R_a = (P_a - P_G) / Q_a

where,
P_a = the afferent arteriole pressure,
P_G = the hydrostatic pressure within the glomerular capillaries,
Q_a = the afferent arteriole flux,
R_a = the afferent arteriole resistance.