Use of rat hepatocytes immobilized in agarose gel threads for biosynthesisof metabolites of potential cytostatics

The aim of this work was to evaluate possibility of use of the rat isolated hepatocytes immobilized in agarose gel and continuously perfused for produ ction of needed metabolites of two potential cytostatics, benfluron (5-(2-d imethylaminoethoxy)-7-oxo-7H-benzo [c] fluorene) and oracin (6-[2-(hydroxye thyl) amino-ethyl]-5,11-dioxo-5,6- dihydro-l 1H-indeno [1,2-c],2-c]isoquino line). The rat isolated hepatocytes obtained by two-step collagenase perfus ion method were immobilized in agarose threads and perfused in a small bior eactor under a recirculation regimes. Biosynthesis of 9-hydroxybenfluron an d 3-hydroxyoracin in immobilized rat hepatocytes was studied. Yields of the metabolites of interest in hepatocytes in immobilized and perfused rat hep atocytes was compared to production of metabolites in hepatocyte suspension and in rats in vivo. 9-hydroxybenfluron was presented during perfusion of immobilized rat hepatocytes in a relatively high amounts but total recovery all forms of benfluron was very low due to especially high binding to comp onents of thr:perfusion system. More effective method remains the productio n of 9-hydroxybenfluron in rats in vivo. A considerable biosynthesis of 3-h ydroxyoracin by immobilized rat hepatocytes in the bioreactor was found. Co ncentration of the metabolite in the perfusate rose continuously during 6 h ours of perfusion. 3-hydroxyoracin production was increased several times w ith use Of immobilized hepatocytes from rats treated for three days with me thylcholanthrene. The yield of 3-hydroxyoracin in rats in viva was comparab ly high but an advantage of in vitro synthesis is a much shorter interval t o obtain the same amount of the metabolite of interest. In spite of some li mitations in compounds exerting high trapping in The perfusion system, the method of the immobilized and perfused hepatocytes can be very useful and e ffective for production of some drug metabolites in biochemistry and pharma cology.