Renal Function in Polycythemic Dogs

¹ From the Department of Medicine, Medical College of Virginia, Richmond, Virginia

Data are presented on dogs rendered polycythemic by chronic exposure to low oxygen tension (8%). The glomerular filtration rate and effective renal plasma flow were decreased (27% and 39%, respectively), while filtration fraction and hematocrit were both increased 22% as compared to control animals. These changes are in accord with data reported in dogs rendered polycythemic by the infusion of red cells. The urinary concentrating mechanism (T^c_HH2O) in milliliters per minute was decreased and T^c_HH2O per 100 ml of glomerular filtrate or T^c_HH2O per kilogram of body weight was also slightly decreased as compared with studies in control animals. In three dogs, the readily available extracellular fluid on several occasions was measured as the volume of distribution of inulin during an 18-month period. The data revealed no significant changes from control studies or during the production of polycythemia.