Antioxidant System Response of Freshwater Mussel Anodontacygnea to Cadmium Exposure

Abstract

Cadmium is one of the widespread toxic substances being hazardous for man as it capable to enter from the environment into animal and plant tissues and spreading along the food chain. We have studied the effect of Cd on the gills and hepatopancreas of the fresh water bivalve mollusks Anodontacygnea. After 12-day acclimation the mollusks were kept for 24 and 72 hours in aquariums with Cd2+ concentrations of 10, 50 and 100 μg/L. Mass-spectrometric analysis has shown that Cd accumulation rate increased with increasing metal concentration in the water. At cadmium concentration of 100 μg/L the mollusk was capable of accumulating up to 0.44 μg of Cd per day. The accumulation of such high metal concentrations in the mollusk tissues did not kill the animals, but signs of oxidative stress, more pronounced in the gills than in the digestive gland, were observed. Exposure to cadmium ions decreased GSH concentration and increase Рx activity in the mollusk gills as early as 24 hours after the beginning of the experiment. Changing the water in the aquarium had a considerable influence on SOD activity in the gills comparable with the effect of the addition of Cd.