Oxygen and chromium transfer in perfused gills of rainbow trout (Salmo gairdneri) exposed to hexavalent chromium at two different pH levels
Putte, I.V.n-Der; Part, P.
Aquatic toxicology 2(1): 31-45
1982
ISSN/ISBN: 0166-445X DOI: 10.1016/0166-445x(82)90004-2
Accession: 016594398
An in vitro study was performed on uptake and transfer of hexavalent chromium, Cr(VI), in gills of rainbow trout (Salmo gairdneri). Gills were perfused according to the isolated head perfusion technique, and externally exposed to Na2CrO4 solutions containing 51CrO42. Experiments were conducted at a concentration of 10 mgl Cr and at pH values of 8.1 and 6.5. The results show that the transfer of chromium is directly coupled with the transfer of oxygen from the external solution to the internal perfusion medium. Under similar conditions of oxygen transfer, however, chromium transfer was significantly more effective at pH 6.5 than at pH 8.1. In addition more chromium was accumulated by the gill tissue at the lower pH. Gill preparations of trout which had been pre-exposed in vivo for 4 days to 10 mgl Cr(VI) at pH 6,5, exhibited an impaired oxygen transfer. This could be well explained by the structural alterations seen after histological examination of the perfused gills.