CHANGES IN PLASMA AND LIVER GLUTATHIONE LEVELS IN ATLANTIC SALMON SALMO-SALAR SUFFERING FROM INFECTIOUS SALMON ANEMIA (ISA)

The levels of reduced glutathione (GSH) in plasma and liver in healthy Atlantic salmon Salmo salar and salmon suffering from infectious salmon anaemia (ISA) were measured using high-performance liquid chromatography (HPLC). The infected salmon had an increased level of plasma GSH Compared to controls, the mean values being 72.31 +/- 11.56 and 52.8 +/- 2.92 muM, respectively. The increased GSH level in plasma was found to be significant (p < 0.0001, unpaired t-test) and may be a result of intracellular release. The hepatic GSH level was significantly lower in the infected salmons compared to controls (p < 0,0001, unpaired t-test) and the mean values were calculated to be 1618.7 +/- 543.7 and 2512.1 +/- 326.9 nmol g-1 liver (wet wt), respectively. A decrease in hepatic GSH of up to 70 % in diseased fish compared to controls was observed. Such low levels of GSH in the liver may affect the capability of this organ in the transformation and excretion of xenobiotics from the body.