HEAT-SHOCK PROTEINS EXPRESSION IN FISH CENTRAL-NERVOUS-SYSTEM AND ITSPOSSIBLE RELATION WITH WATER ACIDOSIS RESISTANCE

The expression of 70 and 60-kDa heat-shock proteins (HSP70 and HSP60) and glial fibrillary acidic protein (GFAP), determined by immunoblotti ng and immunohistochemical methods, was studied in fish neural tissue; moreover; the possible correlation between the expression of these pr oteins in neural tissue and fish acidosis resistance was also examined . The HSP and GFAP content was analyzed in four different teleostean f ish species (gourami, carp, goldfish and trout) under control conditio ns and in carp under experimental conditions to induce HSPs expression . Under control conditions, HSP70 and HSP60 expression was similar in gourami, carp and goldfish, but gourami had the highest acidosis resis tance; trout had the lowest HSP70 and 60 expression and lowest acidosi s resistance. The HSP expression pattern was mainly neuronal under con trol conditions. HSP expression was induced in carp and the effect of this induction on acidosis resistance was studied. Two methods were us ed for HSP induction in carp: acid shock (2 h at 4.5 pH) and heat shoc k (2 h at 33 degrees C). A high acidosis resistance, although non-sign ificant, was observed after heal pretreatment. An important HSP expres sion was detected in glial cells after induction. GFAP expression show ed no association with acidosis resistance under either control or exp erimental conditions. (C) 1998 Elsevier Science Ireland Ltd. All right s reserved.