Response of the nucleolar activity in the gill and liver of the neotropical silverside, Odontesthes bonariensis (Pisces: Atherinidae) exposed to sublethal waterborne concentration of two heavy metals -Cd(II) and Cr(VI)- with different mechanisms of action

CARRIQUIRIBORDE P.; DULOUT F.N.; DE LUCA J.C.; RONCO A. E.

Manaos, Brasil

Congreso; VI International Congress on the Biology of Fish; 2004

Physiology Section, American Fisheries Society

In the present study the response of the nucleolar activity was assessed in the gill and liver of the Neotropical silverside Odontesthes bonariensis (Pisces: Atherinidae) exposed to sublethal waterborne concentrations of Cd(II) and Cr(VI) during 0.5, 1, 2, 4, 6, 12, 24, 48, 192 and 384h. In the gill, the effect caused by Cd(II) and Cr(VI) on nucleolar volume (NV) and nucleoli number (NN) were equivalent; in the liver the response of the nucleolar parameters were different depending on the metal. Findings can be explained in terms of the current knowledge of nucleolar physiology and the mechanism of action of each element.