Isolated perfused rat kidney and liver combined

Abstract

Interaction between hepatic and renal metabolism is found in many endocrine systems. We therefore developed a new experimental model, combining the isolated perfused rat kidney and rat liver. Krebs-Henseleit buffer with bovine serum albumin 67 g·1⁻¹ and amino acids was recirculated to both organs through two rolling pumps, four 8 μm Millipore filters and two specially designed membrane lungs. The kidney was cannulated by a modification of the technique described by Nishiitsutsuji-Uwo 1967 and the liver was cannulated by a modification of the technique described by Hems 1966. Kidney function: Perfusion pressure 12.4±1.1 kPa (93±8 mmHg), flow 28±6 ml·min⁻¹·g⁻¹, FR_Na 94.0±2.9%, GFR 491±191 μl·min⁻¹·g⁻¹, urine production 48±34 μl·min⁻¹·g⁻¹, FE_K 60±36%. Liver function: Flow 25 ml·min⁻¹ (fixed), portal vein pressure 12±3 cm H₂O, bile flow 0.18±0.13 ml·h⁻¹, oxygen consumption 2.0±0.2 μmol·min⁻¹·g⁻¹. Only minor differences were found between single perfusions (N=25) and combined perfusions (N=6). We conclude that it is possible to combine the isolated perfused rat kidney and rat liver without impairment of the function of either.