Gluconeogenesis from lactate and pyruvate in the isolated liver cells of the silver eel was about 2.5 times higher than that in the yellow eel liver, but gluconeogenesis from alanine in the silver eel liver was not different from that in the yellow eel liver. O₂, consumption and the incorporation of CO₂ in liver cells of the silver eel were increased by the addition of ¹⁴C-lactate by 1.5, and 5.3 times higher than those in the yellow eel. There was no increase of O₂ consumption in the liver cells of the silver eel by the addition of¹⁴ C-glucose, and the incorporation of ¹⁴C-glucose into CO₂ was one tenth of that in the yellow eel. The addition of ¹⁴C-palmitate did not increase O₂ consumption in the liver cells of the silver eel, but the incorporation into CO₂, was about 2 times higher than that in the yellow eel liver.
From these results it is suggested that lactate and alanine were utilized as a substrate for gluconeogenesis and an energy source in the liver cells of the silver eel, respectively. It is also suggested that the utilization of glucose and palmitate as energy source was low in the silver eel liver.
Ketogenesis in the silver eel liver was lower than that in the yellow eel liver. Acetoacetate production in the silver eel liver was one fifth to that of the yellow eel liver.