Comparative baseline levels of mercury, Hsp 70 and Hsp 60 in subsistence fish from the Yukon-Kuskokwim delta region of Alaska

In subsistence fish; northern pike (Esox lucius), burbot (Lota lota), whitefish (Coregonus nelsoni), grayling (Thymallus arcticus) and sheefish (Stenodus lencichthys), we determined the Hsp 60 and Hsp 70 levels in 31 samples from adult fish gills. A dot-blot analysis using antibodies to either Hsp 70 or Hsp 60 showed the average Hsp 70 concentration was 9.1 microg/mg protein, while the average Hsp 60 concentration was 147.4 microg/mg protein. Mercury levels in muscle tissue in these fish averaged 0.382 ppm. Using a subset of samples (n = 24), we determined that the major component in the muscle of Alaskan subsistence fish was methyl mercury. No correlation was observed between Hsp 60 or Hsp 70 expression in gill tissue and mercury concentrations in muscle tissue. Hsp 60 and Hsp 70 protein levels in the gills were correlated.