INFLUENCE OF 48 HOURS OF COLD-STORAGE IN UNIVERSITY-OF-WISCONSIN ORGAN PRESERVATION SOLUTION ON METABOLIC CAPACITY OF RAT HEPATOCYTES

Background/Aims: Suspensions of isolated hepatocytes are a valuable to ol to study liver functions, For optimal use of the isolated hepatocyt es, methods are needed to preserve the hepatocytes while maintaining t heir viability, metabolic and transport functions, Until now little ha s been known about the maintenance of the drug metabolism capacity and energy state, measured by the so-called energy charge (ATP+1/2ADP)/(A TP+ADP+AMP), in hepatocytes after storage in University of Wisconsin c old storage solution (UW), Consequently, we investigated whether UW, o riginally designed to preserve organs for transplantation, was suitabl e for preservation of isolated rat hepatocytes with respect to the mai ntenance of drug metabolism and levels of energy-rich substrates. Meth ods: Viability of the isolated rat hepatocytes was determined by trypa n blue exclusion, ATP content and energy charge after 24 and 48 h of s torage in UW at 0 degrees C, Phase I and II metabolic functions of the cells were studied by measuring the cytochrome P450 content and the m etabolic rate of lidocaine and 7-ethoxycoumarin. Results: During 48 h of storage of hepatocytes in UW both phase I and phase II metabolism a re preserved at control levels, After storage, the viability of the he patocytes was not changed significantly, and the cells maintained prop er cellular ATP content and overall energy charge. Conclusions: These results imply that hepatocytes from a single isolation can be stored i n UW solution and used for metabolism experiments for 3 consecutive da ys, allowing a reduction in the use of experimental animals.