新型聚胺基糖表面处理氧化纤维口服吸附剂对肾衰模型鼠的研究

用一种新型聚胺基糖表面处理氧化纤维口服吸附剂（ＣｇｉｔｉｓａｎＤＡＣ）对正常和慢性肾衰模型鼠进行了尿素、氨的体外吸附实验研究，ＣｈｉｔｏｓａｎＤＡＣ在用大鼠胃肠内容物的上清液进行的体外研究中表现出较高的吸附能力。而活性炭Ｋｒｅｍｃｚｉｎ对这些物质的吸附能力则较差。用含５％的ＣｈｉｔｏｓａｎＤＡＣ饲料喂养正常大鼠３周后，其于粪重量、粪内水分含量及粪中含氮量明显增加，而蛋白质表面吸收率则下降。部分结扎肾动脉制成慢性肾衰大鼠模型，用含或不含５％ＣｈｉｔｏｓａｎＤＡＣ的饲料喂养２个月。前者血中尿素氮浓度明显降低，但和后者相比，它们尿中的尿素氮含量无明显差异。提示ＣｈｉｔｏｓａｎＤＡＣ在胃肠道内对尿素和氨的吸附而促进了这些物质在粪中的排泄．ＣｈｉｔｏｓａｎＤＡＣ可降低血浆肌酐浓度，增加肌酐清除率和血红蛋白浓度。而且组织学检查表明服用ＣｈｉｔｏｓａｎＤＡＣ的大鼠其肾小球硬化程度有所减轻。这些观察提示服用ＣｈｉｔｏｓａｎＤＡＣ引起的蛋白质表面吸收率下降，干粪重量、粪内水分含量及其尿毒素排泄的增加，可能在改善慢性肾衰大鼠肾功能方面起着重要作用。

Effects of chitosan-coated dialdehydle cellulose,a newly developed oral adsorbent on normal and chronic renal failure rats

ffects of chitosan coated dialdehyde cellulcoe(chitosan DAC),a newly developed oral adsorbent for urea and ammonia were examined in in vitro adsorption study and in normal and chronic renal failure rats.Chitosan DAC showed a high adsorption capacity for urea and ammonia in in vitro study with diluted supernate of rat gastrointestinal fluid.On the other hand, Kremezin,an oral charcoal adsorbent(AST-1 20)showed little effect on these subetances.In normal rats fed on a diet containing chitosan DAC(5%content)for three weeks,the fecal dry weight,water content and nitrogen content were markedly increased and the apparent protein ratio was decreased.Chronic renal failu re rats induced by twrtial ligation of renal arteries were fed on standard diet with or without chitoan DAC(5%content)for about two months. Rats received chitusan DAC showed significant decrease of blood urea nitrogen while there was no difference in urinary excretion of urea nitrogen compared to rats received normal diet.This resul t suggests an increased excret ion of urea and ammonia which were adsorbed byDAC from the gastrointestinal tract into the feces, Chitosan DAC treatment decreased serumcreatinine,and increased creatinine clearance and serum hemoglobin concentration.Furthermore,histological examination showed an amelioration of glomerular sclerosis indexin chitosan DAC-treated rats.These obervations suggest that decreased apparent protein ratio and euhanced excretionof not ouly so-called uremic toxins containing urea but also fecal volume and water contentby chitosan DAC treatment might play an important role in improvement of renal functionin chronic renal failure rats.