Abstract
It has been suggested that progression of renal failure can be altered by the manipulation of dietary protein. This study examined the effects of dietary protein on renal function and renal histopathology with or without oral adsorbent AST-120 in chronic renal failure rats induced by partial renal infarction. The uremic rats with average serum creatinine of 1.8 mg/dl were fed with high (36%), normal (24%), or low (14%) protein diet with or without AST-120, in which the content of inorganic phosphate was adjusted to the same level. The survival rates were deteriorated by the increase in dietary protein. Blood urea nitrogen and uremic peak 2a detected by LC were elevated with the increase in dietary protein loading, however, serum creatinine and creatinine clearance were not changed among these three dietary groups. The renal histopathology one month after induction of renal failure showed that high protein dietary groups was significantly lighter in glomerular and interstitial lesions than normal protein groups either with or without AST-120. Judging from the blood biochemistries just before death, high dietary protein group died of uremia with lower serum creatinine and higher creatinine clearance than normal dietary group. Administration of AST-120 for 2 weeks improved the blood level of creatinine, peak 2a and survival rate, but did not improve renal histology. The effect of AST was more prominent in high protein group, but seems to be additive even in protein restricted group, removing some uremic substances through gastrointestinal tract. More detail is to be clarified by further long term study.
