The effects of PGI2 analog (OP-41483) on perfused porcine liver

The effects of a prostacyclin analog OP-41483 on energy metabolism were studied in an isolated porcine liver perfused with human blood for 8 h. OP-41483 was administered intravenously at a rate of 0.3 microgram/kg/min during the procurement and into the perfusate at a rate of 1.0 microgram/min during perfusion. Acetoacetate, beta-hydroxybutyrate, lactate, and pyruvate were measured before perfusion and at 1, 2, 3, 5, and 8 h after perfusion, from which values the ketone body ration (acetoacetate/beta-hydroxybutyrate, KBR), reflecting the redox state of liver mitochondria, was calculated. In the OP-41483 group, KBR increased rapidly from 0.34 to 0.95, 1.61, 1.51, 2.35, and 2.04, and lactate decreased rapidly from 9.81 to 6.30, 4.51, 3.22, 2.39, and 1.33 mmol/L at the respective hours after perfusion. There were significant differences after 3 h of perfusion as compared with the control group (p less than 0.05). These results suggest that administration of OP-41483 causes an increase in mitochondrial NAD+/NADH ratio (oxidized and reduced forms of free nicotinamide-adenine dinucleotides), leading to an enhancement of the metabolic capacity of the perfused liver.