The Experimental Studies Of The Influence On Liver Regeneration And Liver Function Of Rabbits After Partial Hepatectomy By Different Infusion Routes Of Total Parenteral Nutrition(tpn)

The Experimental Studies of the Influence on Liver Regeneration and Liver Function of Rabbits after Partial Hepatectomy by Different Infusion Routes of Total Parenteral Nutrition (TPN) BACKGROUND Parenteral Nutrition (PN) has been widely used since Dudrick and Douglas Rhoad use it successfully in 1967. It begins to use in 1977 and get a well clinical effect in our country. Following with the extensive use of PN, it has been found that Long-term PN is accompanied by the damage of liver function including hepatic insufficiency, fatty degeneration ,cholestasis and fibrosis although PN could replace the function of gestrointestinal tract, keep the growth development and metabolic balance. A lot of investigations on the nutritive constituent and formuls of nutrition had been made and the technique of PN was advanced and the complication of PN decreased significantly. But the routes of nutrient infusion were almost via central or peripheral veins at present and the nutrient was escaped from the absorbtion and metabolization by the liver and gut. There are little attention has been paid to the routes of infusion. Because infusion via the portal veins was more on the verge of physiological conditions ,the nutrient substance absorbed and metabolized by the liver first and the bioavailbility of nutrient was promoted from the veiw of nutriology. There are some experimental investigations on the feasibility and potential advantages of intraportal nutrition although it has been reported that this technique may also lead to the damage of liver function. Joyeux (1974), Piccone (1980) , Fairman (1983) and Bozzetti (1993) heve proved that there are a significant advantage of utilizing animo acid , promoting protein synthesis and maintaining the nitrogen balance at intraportal nutrition group. So it is very important to research the nutriologic effect of PN via portal veins. It has been proved that the liver regeneration was influenced and regulated by many factors, such as gene , hormone, cytokine, nutrition and so on. But nutrition as the substrate of liver regeneration has a unsubstitutive role on liver regeneration. Malnutrition or postoperative insufficiency of nutrient absorbtion will reduce liver DNA synthesis, drop cell spilt and restrain liver regeneration. Following with the partial hepatectomy , liver dysfunction, disorder of nutritonal metabolism and insufficiency uptake of nutrition will happen. The only way to correct it is promoting liver regeneration. Recent researche has focused on this way and the clinical and experimental studies have identified that PN is in favor of liver regeneration. Because intraportal nutrition was more tally with physiological condition, we believe that further studies will be necessary to liver regeneration. OBJECTIVE 1 .To establish an animal model of equal part hepatectomy and a methed of portal vein intubation. 2.To study the influence of PN via portal vein and central vein on liver regeneration and liver function on the basis of this animal model. 3. To investigate the possibility of promoting liver regeneration and recovery of liver function by PN via portal vein and provide a theroretical foundation for clinical treatment. MATERIALS AND METHODS An animal model of equal part hepatectomy and a methed of portal vein intubation were established According the experimental model of rat which had been founded. Three groups were studied: Group I control group: these animals were only subjected to partial hepatectomy .Group II: these animals were infused 6 day...