抄録
Effects of aminoguanidine (AG) on binding of glucose and pyridoxal phosphate (PLP) to albumin, and on glycation reaction of cytosolic aspartate aminotransferase (CAST) were examined in an in vitro system. AG was found to inhibit not only glycation of albumin but binding of PLP to albumin, indicating that distribution of PLP into tissues is inhibited by AG. AG bound to PLP directly to produce a new compound, and in this manner AG inhibited cAST activity. AG could also inhibit glycation of CAST and the extent of inhibition was varied with sugars used. It appears that, although AG is a useful inhibitor of gly-cation proteins, it may be toxic from the viewpoints of vitamin P6 as an essential nutrient and also PLP-dependent enzymes.