Plasma and organ biochemistry Clarias gariepinus exposed to monoaromatic, Toluene

Abstract

The effect of toluene on enzymes; Aspatate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) in the plasma, organs (gills, kidney, liver) and muscle of Clarias gariepinus was assessed. The activity of AST in the gill was variable among the treated group and between the treated groups and the control with increase in all the concentrations (129.4 – 976%) above the value of the control (42.50 ± 28.72 IU/L). Activity of ALT in the gill was gradually raised from 50 ppm to a peak (187.50%) at 125 ppm. Although the ALP had the highest activity in the gill in comparison to other enzymes it was variable with inhibitions. Toluene caused excitation at 75 and 125 ppm were more than thrice and twice respectively that at the control in the kidney. It caused increase in the activity of ALT with more than 6x (25 ppm), 9x (75 ppm) and 15x (125 ppm) that of the control. However, the activity of ALP in the kidney was generally unaffected by the exposure at the other concentrations. There was general excitation of AST activity in the liver with higher levels of excitation, 25 – 40% at 25, 75 and 125 ppm. A raise in ALT activity was recorded in all the exposure. A concentration-dependent increase was observed in activity of ALP in the liver 299, 479 and 596% above the control value, 46.00 ± 34.84 IU/L. There was both excitation inhibition of AST activity in the muscle tissue of the fish. There was a sharp decline of 69 and 55% at 50 and 100 ppm in ALT activity and enhanced activity of 321, 179 and 227% at 25, 75 and 125 ppm, respectively above the control value. ALP activity was excited in the muscle in all the test concentrations (maximum, 90% at 25 ppm). There was a sharp decline in the activity of AST in the plasma with the least value at 75ppm, 64% lower than the control value. All concentrations toluene elicited the activity of ALT in the plasma.. The increase were 3.5x, 2.5x, 4.5x, 2.25x and 5x at the exposure concentrations (25, 50, 75, 100 and 125 ppm) respectively, relative to the control values. The relative activity of AST in the organs generally followed the pattern: muscle > liver > gill > kidney> plasma and that of ALT activity, muscle > kidney > liver > gill > plasma and ALP was kidney > muscle > liver > gill > plasma.

Keywords: Toluene, Clarias gariepinus, Aspartate transaminase, Alanine transaminase, Alkaline phosphatase

Animal Research International (2012) 9(3): 1645 – 1653