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