Anesthesia with benzocaine and MS-222 in juveniles of tambaqui Colossoma macropomum: effects on oxidative stress parameters
In the present study, the effects of two anesthetics (benzocaine and tricaine methanesulfate (MS-222) on biochemical parameters in the tissues of juveniles of tambaqui Colossoma macropomum were evaluated. 80 juveniles of tambaqui were used, which were anesthetized with benzocaine (BZ - 100 ppm) or MS-222 (TR - 240 ppm). Two other groups, called controls: water control (without anesthesia) and alcohol control (exposure to alcohol PA) also underwent the same procedure. After anesthetic induction 10 fish / anesthetic / time samples were euthanized at times 3, 12 and 24 hours to collect tissue samples (gills, liver and brain) which were used to analyze the activity of the antioxidant enzyme glutathione S-transferase (GST), as well as cellular lipoperoxidation (TBARS) and total antioxidant capacity (ACAP),at different sample times. In the gills, there was an increase in ACAP in the BZ treatment in relation to the TR and the control group at 12h. The liver showed a reduction in ACAP in the time of 12 h for the treatment TR compared to the control. The treatments BZ and TR in 24 h showed an increase in ACAP in relation to the control. The activity of the GST enzyme increased in the gills for the treatments BZ and TR in the times of 3 and 12 h in relation to the control. The liver showed an increase in BZ treatment in 24 h and for TR in times 3 and 24 h in relation to the control. There was a decrease in lipid damage in the gills (BZ and TR) and in the brain (TR) in 24 h compared to the control. According to the results, we conclude that the anesthetics used in this work, at doses of 100 ppm (BZ) and 240 ppm (TR) did not cause oxidative damage in the juveniles of tambaquis,but they are capable of producing an antioxidant response to prevent lipoperoxidation and cause detoxification of the body.