Short term cadmium intoxication of the shrimp Palaemon serratus: Effect on adenylate metabolism

Abstract

1. 1. Shrimps were exposed for 96 hr to various concentrations of cadmium under laboratory conditions. The LC 50 was around 4 ppm Cd in water, which corresponded to 0.180 μg/g wet weight of cadmium in tail muscles. 2. 2. The effect of various concentrations of cadmium on adenylates was analyzed in tail muscles: At subletal cadmium concentrations, no variation of ATP, ADP and of the adenylate sum occurred, while the AMP concentration began to decrease from 0.06 ppm. At the LC 50, the ATP, ADP and AMP concentrations dropped acutely, the ATP/ADP ratio increased acutely. The apparent equilibrium constant of the adenylate kinase reaction increased significantly from 2 ppm Cd, indicating an impairment in energetic metabolism. Cadmium intoxication did not influence the value of the adenylate energy charge.