The Royal College of Surgeons (RCS) rat is an established animal model used to study human retinal dystrophies. This study investigated whether kidney dysfunction accompanies the eye abnormalities seen in this model. Overnight urine collection procedures were used to measure protein excretion in 2, 12, and 22 month old female pigmented RCS rats and control rats (RDY). Clearance experiments were performed in anesthetized rats to measure glomerular filtration rate (GFR) and renal plasma flow rate (RPF). There was an age-related increase in protein excretion in both RCS and RDY rats, but the protein excretion was significantly higher in the RCS rats at 2 and 22 months of age. Whole kidney GFR and RPF were significantly lower in the 22 month old RCS rats, when compared to age-matched RDY rats. These findings suggest that the RCS rat exhibits both kidney and eye abnormalities. / Department of Physiology and Health Science