[Effects of copper and cadmium ions on protective enzyme activity in Oncomelania hupensis]

To evaluate the effects of Cu²⁺ and Cd²⁺ at different concentrations on superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activity in Oncomelania hupensis.

Cu²⁺- and Cd²⁺-containing solutions were prepared at 7 concentrations, and O. hupensis snails were exposed to the solutions for 24 h, of 15 snails in each concentration. Then, the snail body was collected following removal of the snail shell and homogenated, and the SOD, CAT and POS activities were detected in the supernatants.

With the increase of the Cu²⁺ concentration, the SOD activity appeared a rise followed by a reduction in O. hupensis snails, and the CTA activity appeared a decline-rise-decline tendency, while the POD activity showed a tendency towards rise followed by decline. With the increase of the Cd²⁺ concentration, the SOD activity appeared a rise followed by a reduction in O. hupensis snails, and the CTA activity appeared a decline- rise- decline tendency, while the POD activity showed a decline-rise-decline tendency.

Exposure to Cu²⁺ and Cd²⁺ at high concentrations results in a decline in the activity of SOD, CAT and POD in O. hupensis at the same time.