Inhibition by tributyltin of herring skeletal muscle lactate dehydrogenase activity

The activity of herring (Clupea harengus) skeletal muscle lactate dehydrogenase (EC 1.1.1.27) LDH-A4 isoenzyme was examined in the presence of tributyltin chloride (TBT). This paper reports the in vitro inhibition of LDH activity with increasing concentration of TBT. Bovine serum albumin (BSA) added to the LDH-A4 isoenzyme prior to the addition of TBT was able to protect enzyme activity against inhibition by this toxicant. The observed protection of LDH-A4 activity increased with increasing BSA concentration in the incubation medium. The results suggest that the presence of BSA could protect LDH activity from direct binding of TBT to LDH.