The effects of fructose feeding on glomerular structure in the rat.

hydrate (60%), but also of protein (20%), lipid (5%), calcium (0.6%). phosphorus (0.5%), sodium (0.5%), and potassium (0.5%). Rats were provided with food and water ad tibitum for 1 2 months. Body weight, systolic blood pressure, and blood glucose were measuned monthly for 8 months and blamonthly thereafter. Urine albumin excretion rate was measured at 4, 8, and 12 months. Blood samples were obtained at 12 months for measurement of serum insulin, tnglyceride, and cholesterol and blood glucose concentrations. For these measurements, food was removed at ‘-‘8:00 am. and blood was taken at 1 :00 p.m. Values for each rat were calculated as the mean of values for two blood samples obtained 1 wk apart. After the final blood sample was obtained, animals were anesthetized with Inactin (1 00 mg/kg ip) and kidneys were perfusion fixed for morphologic analysis. Kidney tissue was embedded in methacrylate. and the prevalence of glomenular sclerotic lesions and mean gbomenular volume were assessed as descnibed previously ( 1 1 ). Blood pressure was determined by the tail cuff method, and blood glucose was measured with chemical strips (Gbucameter; Miles, Elkhart, IN). Urine albumin was determined by rate nephebometry ( 1 1 ). Serum insulin was determined with a commercially available kit (Incstar, Stillwater, MN). Serum cholesterol and triglycerides were determined by standard clinical methods (Ektachem; Kodak, Rochester, NY). Tissue specimens could not be analyzed in two corn-fed rats and three fructose-fed rats because of technical errors.