A Perfluorochemical Oxygen Carrier (Fluosol-43) in a Synthetic Medium Used for Perfusion of Isolated Rat Liver

An emulsion of perfluorotributylamine (Fluosol-43) was used as substitute for the gas-carrying function of erythrocytes in a synthetic medium for perfusion of isolated rat liver. The efficiency and effect of this synthetic gas-carrier were evaluated from measurements of the concentrations of rat albumin, the unsaturated vitamin B.,-binding capacity of small-molecular-size vitamin B₁₂-binding proteins (UBBC of SBP), urea nitrogen, glucose, sodium, potassium, alanine amino transferase (ALAT) in the medium, and the incorporation of ¹⁴C-lysine into the circulating proteins. Secretion of bile, portal pressure, PO₂, PCO₂ and pH in the affluent and the effluent mediums were also measured. The results demonstrate that the oxygen-carrying capacity of the medium and the metabolic functions of the liver were higher, and the liver damage less, when the medium included Fluosol-43 than without it. The albumin synthesis and the secretion of bile were as high as has been reported for perfusions with erythrocytes. This indicates that the oxygen carried by the Fluosol-43 was utilised by the liver, and that the metabolic functions were not adversely affected during 4 h of perfusion by the medium containing Fluosol-43.     

Release of Vitamin B12-Binding Protein from Isolated Rat Liver Perfused with a Synthetic Medium

The unsaturated vitamin B₁₂-binding capacity (UBBC) of the small molecular size vitamin B₁₂-binding protein (SBP) release and albumin release into the medium and the fluid pressure in the portal vein were studied with respect to their ability to reflect the state of isolated perfused rat liver. The liver was perfused in vitro with a synthetic medium either with or without a gas carrier. Liver damage was induced by hypoxia or noradrenalin. Variations in experimental conditions resulted in different patterns of parameters reflecting different aspects of the liver state. The fluid pressure in the portal vein reflected sensitively the circulatory state but is not always a criterion of the general condition of the isolated liver. The albumin release is a criterion of functional state but did not always reflect liver damage. However, the amount of UBBC of SBP released into the medium is a parameter reflecting sensitively the functional capacity of the liver to produce protein and also seems to indicate liver damage. The use of this parameter provides supplementary information that cannot be obtained by either of the two more conventional parameters.