Summary:In the mixed body lymph of the thoracic duct and in the defined organ lymph of the liver and the intestine, the catalytic activity concentrations of up to sixteen enzymes arid the concentrations of albumin and protein were determiiied, äs well äs the transport rate of these substances and their lymph/plasma ratio. Thoracic duct lymph specimens were obtained from an extracorporeal lymph shunt in anaesthetized and conscious dogs and from short-term fistulas in anaesthetized rabbits, rats and mice. Additionally, rabbits and rats underwent passive motion of the bind limbs in another experimental trial. Thoracic duct flow in anaesthetized dogs is only half that seen in conscious dogs, due to bypassed muscular lymph. A similar flow change is seen during passive motion of bind limbs in anaesthetized rabbits and rats. From a literature review of flow in the four main lymphatics of the body, it is concluded that the thoracic duct flow should account for 50-70% of total body lymph flow. In the anaesthetized stäte, flow is mainly of visceral origin. In the conscious state and during passive motion the ihäteased flow is of miisfcular origin. In the latter case, the catalytic activities of enzymes like lactate dehydrogefiase, maläte döhydfogenase, creatine kinase, aldolase and phosphohexose isomerase, increase in lymph äs doels their lympH/plasma ratio. These enzymes have high catalytic activities in muscle* Their transport into the blöod increases 2-3-fold, due tö a doubling of l^mph flow. Reported data for anaesthetized and immobile animals theffcfore far tinderestimate the significahce of thoracic duct enzyme transport. Liver lymph was obtaihed frdftl anaesthetized dogs and rabbits. Our Unding that lymph catalytic activity for several enzymes is higher than in plasma iS not compatible with the proposed delivery of plasma proteins directly into the sinusöidäl space without priör ffl&ing with the Space of Disse. Enzymes in liver lymph should derive from parenchymal afld endothelial liiiiflg Sfells. Their site of delivery from the hepatocyte seems different from that of proteins. Liver lymph is an important transport route of enzymes into the blood. Intestinal lyiflßh was sampled from anaesthetized dogs, rabbits and rats. It was shown that most enzymes from the intestine are primarily released into the interstitial space and from there aie transported via the lymph into the blood. Thoracicus-, Leber-und
Katalytische Enzymaktivitätskonzentration in Ductus
