[Inhibitory effect of uremic fluorescent substances on the cellular energy generation]

The toxicity of uremic fluorescent substances (F-ure) in hemofiltrates of a dialysis patient on the respiration of rat liver mitochondria was studied in comparison with some fluorescent substances (F-cir) in a cirrhosis urine. These substances found in both the body fluid of chronic disease were fractionated by hydrophobic HPLC. And the characteristic of (1) F-ure and (2) F-cir was as follows: the hydrophobicity based on Sasagawa's constant, (1) 1.1 approximately 1.3 & (2) 1.8; lambda max in UV spectrum, (1) 231, 356 nm & (2) 220 approximately 230, 290 nm; Em in fluorescence, (1) 461 nm & (2) 361 or 504 approximately 7 nm. When F-ure was added into mitochondrial respiratory medium, the respiration of succinate (State 4) decreased about a half in the presence of phosphate and succinate/ADP respiration (State 3) was much suppressed. And about a quarter of this suppression was released by an uncoupled (SF-6847), whereas F-cir on the state 3 respiration showed to be stimulative effect in like manner of uncoupler. The toxicity of uremic fluorescent substances on cellular energy generation could be demonstrated by decreased respiration of mitochondria.