Beneficial effect of combined 3,5,3'-triiodothyronine and vasopressin administration of hepatic energy status and systemic hemodynamics after brain death.

The influence of combined replenishment of L-3,5,3'-triiodothyronine (T3) and vasopressin (antidiuretic hormone [ADH]) on both hepatic metabolism and systemic hemodynamics was assessed in brain-dead dogs. Arterial ketone body ratio (AKBR) was measured as a parameter of hepatic metabolism, which reflects the redox state (free nicotinamide adenine dinucleotide/reduced nicotinamide adenine dinucleotide) of liver mitochondria. Mean arterial blood pressure (MAP) was significantly decreased from 110.4 +/- 3.8 to 44.4 +/- 1.7 mmHg, at 1 hr after completion of brain death (P less than 0.01). In the control group AKBR was maintained thereafter at near control value of 1.0 with a significant decrease in serum lactate concentration in spite of marked hypotension. T3 infusion at a rate of 1 microgram/kg/hr elevated the AKBR but did not elevate MAP. Vasopressin infusion at a rate of 0.1 U/kg/hr sustained AKBR and elevated MAP significantly at 1 hr after administration but tended to decrease thereafter. Combined administration of T3 and ADH elevated the AKBR to about 2.0, and MAP was restored to near-normal level. Other parameters such as glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and lactic dehydrogenase, reflecting liver cell injury and serum creatinine, and blood urea nitrogen as renal function, were maintained within normal range. These results indicate that combined T3 and vasopressin administration has a beneficial synergistic effect on both hepatic energy metabolism and systemic hemodynamics without any detrimental influence to other conventional parameters. Therefore, it is suggested that this combined administration may contribute to the management of potential multiorgan donors.

Preferential utilization of glucose over melibiose, and vice versa, in a pts mutant of Salmonella typhimurium.

Preferential utilization of glucose and melibiose was investigated in wild type cells and in pts mutant (ptsI-leaky) cells of Salmonella typhimurium. A typical diauxic growth and preferential utilization of glucose over melibiose were observed in wild type cells when these two sugars were added as carbon source. Similar results were obtained with a pts mutant (SB1476) although utilization of glucose was slow. When cyclic adenosine 3',5'-monophosphate (cAMP) was added to the culture medium to release the catabolite repression, preferential utilization of glucose was still observed in wild type cells. With glucose-induced mutant cells, preferential utilization of glucose was observed in the presence of cAMP. Gradual utilization of melibiose took place when glucose concentration in the medium decreased. Surprisingly, preferential utilization of melibiose over glucose was observed with melibiose-induced and glucose-uninduced mutant cells in the presence of cAMP.

Postoperative recovery of mitochondrial function of the human liver graft procured and preserved with University of Wisconsin (UW) solution.

Changes in arterial blood ketone body ratio (KBR) were investigated in 47 human liver transplantations. Of the 20 grafts preserved with University of Wisconsin (UW) solution, 10 had a cold preservation period of less than 10 h (UWS group) and 10 of more than 10 h (UWL group). In 27 other cases, grafts were preserved with EuroCollins (EC) solution for less than 10 h (EC group). In the EC group, KBR increased over 0.7 within 6 h after reperfusion of the graft in 17 cases (63%) and within 24 h in 7 cases (26%). In the 3 other cases, KBR failed to recover, and these patients underwent retransplantation. In the UW group, KBR recovered within 6 h in 13 cases (65%) and within 24 h in 7 cases (35%). There were no significant differences between the UWS and UWL groups. It is shown that the mitochondrial function of liver grafts preserved with UW solution can be well maintained even after extended preservation periods of more than 10 h.