Effects of in vivo and in vitro dialysis on plasma transaminase activity

The effects of dialysis on plasma glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) were investigated. GOT was measured using Autoanalyzer (SMA) and kinetic (Karmen) methods. Hemodialysis of uremic subjects was associated with a significant increase of GOT (SMA) and GPT (SMA). In contrast, hemodialysis had no effect on GOT (Karmen). However, the SMA method is influenced by substances affecting the blank value. Therefore, the results suggest that the increase in transaminase activities measured by the SMA method are not due to true increases in enzyme activities. Plasma from dialysis patients, obtained prior to hemodialysis, was also dialyzed in vitro. In vitro dialysis of uremic plasma significantly increased GOT (SMA), GOT (Karmen) and GPT vitro dialysis of uremic plasma significantly increased GOT (SMA), OGT (Karmen) and GPT (SMA). The results suggest that an inhibitor of transaminase activity may accumulate in renal failure. In vitro dialysis may remove this inhibitor and thus increase true transaminase activity.