Effect of pesticides on the LDH activity and isoenzyme pattern of carp (Cyprinus carpio L.) sera.

Copper sulphate (CuSO4), paraquat (PQ) and methidathion (MD) all caused tissue necrosis as demonstrated by increased levels of lactate dehydrogenase (LDH, EC 1.1.1.27) in blood sera. The main target of damage is shown by the isoenzymes appearing in the blood sera. The CuSO4 treatment damaged mainly the heart and skeletal muscles. This is indicated by the increased LDH level and the M and H subunits appearing in the isoenzyme pattern of the serum. PQ damaged first of all the gills and methidathion had an effect on the skeletal muscles.