CAT and hydronephrosis: In rabbits with severe hydronephrosis, the Mn-SOD, GR and CAT levels decreased when subjected to perfusion pressure of 60 mmHg or 100 mmHg (p<0.05, Fig 2B); however, the MDA and H2O2 levels in this group increased when subjected to perfusion pressure of 60 mmHg or 100 mmHg (p<0.05, Fig 2B).