The urea cycle enzymes activity and its gene expression in rat hepatocytes are not affected by cold storage in University of Wisconsin solution.

ALMADA L., BELLAROSA C., GIRAUDI P., MAMPRIN M., MEDIAVILLA M., GUIBERT E., TIRIBELLI C. Y RODRÍGUEZ J.

Rosario

Workshop; Primer taller de Criobiología en Ciencias Médicas; 2005

Laboratorio de Investigaciones en Criobiología (UNR)

The Urea Cycle (UC) is the main pathway ofvammonium removal. A deficiency in any of the six classical enzymes of the pathway causes an Urea Cycle Disorder. Hepatocellular transplantation is one of the techniques applicable to treat this disorder. In the present work, we investigated the activities and the relative expression levels of two of the UC enzymes: Carbamyl Phosphate Synthetase I (CPS1) and Ornithine Transcarbamylase (OTC), in isolated hepatocytes preserved up to 120 hr in UW solution at 0ºC, and during the rewarming of these suspensions. During preservation, CPSI showed differences in both parameters measured respect to time 0. OTC remained unchanged in this step. At the end of the rewarming, CPSI and OTC showed values of enzymatic activity and relative mRNA level comparable with the control. Confirming this results, we found that hepatocytes cold preserved up to 120 hr in UW solution showed no difference in their ability to remove a concentration ammonium load respect to freshly isolated hepatocytes. These data indicated that cold preservation of rat hepatocytes up to 120 hr in UW solution followed by rewarming maintain UC enzymes with a behavior similar to freshly isolated hepatocytes.The Urea Cycle (UC) is the main pathway ofvammonium removal. A deficiency in any of the six classical enzymes of the pathway causes an Urea Cycle Disorder. Hepatocellular transplantation is one of the techniques applicable to treat this disorder. In the present work, we investigated the activities and the relative expression levels of two of the UC enzymes: Carbamyl Phosphate Synthetase I (CPS1) and Ornithine Transcarbamylase (OTC), in isolated hepatocytes preserved up to 120 hr in UW solution at 0ºC, and during the rewarming of these suspensions. During preservation, CPSI showed differences in both parameters measured respect to time 0. OTC remained unchanged in this step. At the end of the rewarming, CPSI and OTC showed values of enzymatic activity and relative mRNA level comparable with the control. Confirming this results, we found that hepatocytes cold preserved up to 120 hr in UW solution showed no difference in their ability to remove a concentration ammonium load respect to freshly isolated hepatocytes. These data indicated that cold preservation of rat hepatocytes up to 120 hr in UW solution followed by rewarming maintain UC enzymes with a behavior similar to freshly isolated hepatocytes.