RESUMEN
A time course study on the sublethal toxicity of CuSO4 on tissue carbohydrate metabolites level and their phosphatases activity in Achatina fulica revealed differential response. The levels of total carbohydrates and glycogen in the body mass muscle, foot muscle and hemolymph revealed their involvement in the endogenous derivation of energy during stress. The same metabolites in digestive gland revealed its importance to reproduction and development. The lactate accumulated in all the tissues implied the mechanism of CuSO4 toxicosis in the metabolic acidosis. The decrease of pyruvate in foot muscle, body mass muscle and hemolymph inferred the preponderance of glycolysis in energy derivation. In contrast, the pyruvate concentration in digestive gland revealed its differential response in the stress metabolic sequence of changes, as a unique tissue. The lactate/pyruvate ratio and the calcium content in tissues constitute direct evidences for the snails adaptation to toxic stress.