Stress proteins as a bioindicator in the sub-tropical marine fish, Lutjanus griseus, the gray snapper

278

Abstracts

various degrees of contamination by urban/industrial waste. Sea combers (Serrunus cubrillu) and mussel (Mytilus galloprovinciufis) were collected at the same sites. EROD and BPH activities were measured in microsomes from fish liver, and BP0 (measuring the total benzo(a)pyrene metabolites) and BPH activities were measured in microsomes from mussel digestive gland. Mussel BPH (r = 0.66, p < 0.01) and BP0 (r = 0.37, p < O.OS), fish BPH (r= 0.42, p < 0.05) but not fish EROD (r = 0.29, were correlated with the log of PAH concentration in sediment. The results show that in our conditions BPH activity measured both in mussel and fish is a good marker of PAH contamination whereas EROD activity measured in fish exhibits less significant results.

Stress Proteins as a Bioindicator in the Sub-Tropical Marine Fish, Lutjanus griseus, the Gray Snapper. L. B. NYE. Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida 33149, USA. As increasing demands are made on marine resources, monitoring and understanding the effects of pollution and other anthropogenic changes on marine environments are vital. A well-developed suite of bioindicators in well characterized marine organisms can deliver meaningful and useful information to scientists and managers. Some potentially useful bioindicators are the stress proteins. In the gray snapper, a heat shock (from 23°C to 35°C) for 1 h followed by several hours recovery resulted in an increased production of a constitutive member of the hsp70 family and in the production of an inducible hsp70. These changes were observed in liver tissue from heat shocked animals and in hepatocytes and white and red blood cells heat shocked in vitro. Larger differences were observed between the control and experimental liver and white blood cells than between the control and experimental red blood cells. The differences between the amounts of hsps in the different tissues is being used to decide which hsp and which tissue show the greatest potential for use as a bioindicator. Further experiments are underway to develop the gray snapper as a model and to examine the validity and usefulness of stress proteins as bioindicators in Biscayne Bay, Florida. In particular, the persistence of the stress protein response and the differences between responses to thermal, salinity and chemical stressors are being examined. Proteins are quantificated by western blots or dotblots with commercial antibodies labled with Amersham’s ECL system and imaged with Fotodyne’s Collage software.

Effects of In Viva Induction and Inhibition of Phase 1 and 2 Enzymes on the Toxicity of Malathion to Tilapia. ASOKA PATHIRATNE & STEPHEN GEORGE. Department of Zoology, University of Keluniyu, Sri Lanka and NERC Unit of Aquatic Biochemistry, University of Stirling, Stirling FK9 4LA, UK. The organophosphorus (OP) insecticides are neurotoxicants that have been used for many years to kill insects by causing persistent inhibition of acetylcholinesterase (AChE). The phosphorothionate, malathion, is widely used in many countries to control mosquitos and rice pests. Since many rice ponds are also used for mariculture of important food species,