Kobe Journal of Medical Sciences, 1993

TI: The importance of adenosine metabolism in ischemically damaged canine pancreas during preservation by the two-layer cold storage method.

AU: Hiraoka-K; Kuroda-Y; Saitoh-Y

AD: Department of Surgery, Kobe University School of Medicine.

SO: Kobe-J-Med-Sci. 1993 Dec; 39(5-6): 183-95

AB: The two-layer cold storage method using the University of Wisconsin solution (UW) allows continuous tissue adenosine triphosphate (ATP) production during the preservation period. UW contains 5mM of adenosine which has several mechanisms of action, however, its efficacy is controversial. In this study, at first, we investigated the metabolism of exogenous adenosine during preservation by the two-layer method in the canine pancreas graft subjected to 60 min warm ischemia. High concentration (> 5 mM) of adenosine in Euro-Collins' solution (EC) remarkably increased ATP and total adenine nucleotide (TAN) levels during 24 hr preservation by the two-layer method using EC. Furthermore, experiments with 5 mM of [2-3H] adenosine demonstrated that adenosine was metabolized and incorporated into adenine nucleotides (ANs). However, neither 5 mM of inosine, hypoxanthine nor adenine substituted for adenosine. It was clear that adenosine was directly phosphorylated and converted into ANs. Secondly, the effect of adenosine on the viability of the ischemically damaged pancreas graft was evaluated by graft survival following autotransplantation. The ischemically damaged pancreas grafts were preserved for 24 hours by simple cold storage in EC (group 1), EC with 5 mM of adenosine (group 2), the two-layer method using EC (group 3), EC with 5 mM of adenosine (group 4). Graft survival rates were 0/5 (0%), 1/5 (20%), 0/3 (0%) and 4/5 (80%) in groups 1, 2, 3 and 4 respectively. Adenosine was clearly effective on graft survival via recovering high tissue ATP and TAN levels only in case of the preservation by the two-layer method. We conclude that exogenous adenosine works as a substrate for ANs synthesis and is directly phosphorylated to ANs during preservation by the two-layer method. This is essential to repair damaged cells and maintain cellular integrity, making it possible to preserve ischemically damaged pancreas.