On the pyridoxal-5'-phosphate stimulation of aspartate aminotransferase and alanine aminotransferase in serum and erythrocytes of patients undergoing chronic haemodialysis and with kidney transplants.

Aspartate aminotransferase (AST) determinations in erythrocytes of patients undergoing chronic haemodialysis and with kidney transplants showed that patients receiving vitamin B6 had a smaller relative stimulation rate of AST by pyridoxal-5'-phosphate (P-5-P). In contrast to these results in erythrocytes, the apoAST and apo-alanine aminotransferase (ALT) activities in serum were increased in patients as compared with those of healthy persons. The corresponding relative stimulation rates of AST and ALT by P-5-P addition to the reaction mixture were not changed in the haemodialysis patients, but in renal transplant recipients the relative stimulation rate of AST was significantly smaller and that of ALT was greater.