Enzyme Activities of the Perfused Ex-Vivo Porcine Liver: Importance of a Physiological Perfusate

Abstract

Baker, P. R. & Cuschieri, A. Enzyme activities of the perfused ex-vivo porcine liver: importance of a physiological perfusate. Scand. J. Gastroent. 1974, 9, 65–71. The activities of five cytoplasmic enzymes have been determined in homogenates of livers perfused at normothermia by one of two different systems; isolated perfusion (IP) or auxiliary perfusion (AP). In the IP group livers were perfused in a completely artificial circuit where the essential constituents of the dilute blood perfusate were not replenished, and low levels of pyruvate kinase, sorbitol dehydrogenase, and isocitrate dehydrogenase were found. In the AP group the livers received a ‘physiological’ blood supply directly from a living donor, and these had normal to high enzyme activities. The IP livers had lower values of all enzymes compared with the AP group. The decrease in pyruvate kinase activity was probably due to a deficiency of the L form of this enzyme, since only the fructose-diphosphate-stimulated pyruvate kinase activity was abnormally low. Reduced activity of this key enzyme in glycolysis may be partly responsible for the observed functional impairments of the isolated perfused liver.