Effects of artificial blood (FC-43 emulsion) on myocardial energy metabolism in the rat heart-lung preparation

We have assessed the effects of artificial blood (FC-43 emulsion)on myocardial energy metabolism in the rat heart-lung preparation.Animals were allocated to four groups (n = 8 each group) accordingto the ratio of perfusion blood and FC-43 as follows: group1 = control, perfusion blood only; group 2 = 50% FC-43; group3 = 75% FC-43; and group 4 = 100% FC-43. Hearts were perfusedinitially to a cardiac output of 30 ml min^–1 and meanarterial pressure of 50 mm Hg. Thirty minutes after perfusion,the hearts were freeze-dried for 6 days. Myocardial high energyphosphates (ATP, ADP and AMP) were measured by high pressureliquid chromatography. Myocardial lactate and glycogen concentrationswere measured by enzymatic methods. There were almost no significantdifferences in cardiac output, systolic pressure, right atrialpressure and heart rate among the groups. Oxygen contents ofthe perfusate in all FC-43 groups were significantly lower thanthose in the control group. Myocardial ATP concentrations inrats receiving 50%, 75% and 100% FC-43 were significantly lowerthan those in the control group. In addition, myocardial ADPand AMP concentrations in rats receiving 75% and 100% FC-43were significantly higher than those in the control group. Althoughthere is adequate oxygen-carrying capacity in FC-43 to maintaincardiac function during perfusion, the energy levels in thehearts perfused with FC-43 were lower than those in normal hearts.