Resumo

NUSETTI, Osmar et al. Respuestas inmunológicas y de enzimas antioxidantes en la ostra perla Pinctada imbricata (Mollusca: Pteridae) expuesta a niveles subletales de fuel oil nº6. INCI [online]. 2004, vol.29, n.6, pp.324-328. ISSN 0378-1844.

The immune and antioxidant enzyme defenses in pearl oyster Pinctada imbricata were evaluated after shotterm (7d) exposure to 25 and 100% watersoluble fraction (WSF) of Fuel Oil Nº6, a source of polyaromatic hydrocarbon and heavy metal contamination of marine ecosystems. Lysozyme activity in the digestive gland and the phagocytic activity of hemocytes were measured as humoral and cellular immunological responses, respectively, using heat killed yeast cells as antigen for the phagocytosis assay. The viability and total number of hemocytes were recorded. The detoxifying enzymes Glutathione-S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) and catalase (CAT) were evaluated from the digestive gland and mantle extracts. In the digestive gland the exposure to P. imbricata are sensitive to short-term exposure to Fuel Oil Nº6, suggesting an increased oxiradical flux and biochemical manifestations of oxidative injury in both tissues. These parameters should be considered as potential tools for the biomonitoring of marine environmental contamination.

Palavras-chave : Enzimas Antioxidantes; Estrés Oxidativo; Fagocitosis; Lisozima; Pinctada imbricata.