Inhibition effect of some chemical Anesthetics and hypothermia on the activity of glucose 6-phosphate dehydrogenase from rainbow trout (Oncorhynchus mykiss) erythrocytes in vivo

Many chemical anesthetics and drugs have been used in fish stripping, surgery and transportation, but their undesirable side effects on the body metabolism during treatment are not usually taken into consideration. In this study, we investigated the inhibition effect of some chemical anesthetics, such as Tranquil and tricaine methanesulfonate (MS-222), and hypothermia on glucose 6-phosphate dehydrogenase (G6PDH) activity. The control, initial, 1 h and 4 h values were 41.334 +/- 3.190 EU (g Hb)(-1), 34.586 +/- 5.086 EU (g Hb)(-1), 40.768 +/- 3.430 EU (g Hb)(-1) and 41.957 +/- 3.157 EU (g Hb)(-1), respectively, in hypothermia. These values were 39.470 +/- 2.250 EU (g Hb)(-1), 35.807 +/- 2.000 EU (g Hb)(-1), 32.756 +/- 7.822 EU (g Hb)(-1) and 34.882 +/- 3.452 EU (g Hb)(-1) with Tranquil and 52.910 +/- 2.490 EU (g Hb)(-1), 27.044 +/- 2.750 EU (g Hb)(-1), 39.901 +/- 4.477 EU (g Hb)(-1) and 42.629 +/- 2.593 EU (g Hb)(-1) with MS-222, respectively. Hypothermia, Tranquil and MS-222 showed inhibition effects on G6PDH activity. The inhibition effects of hypothermia and Tranquil were not statistically significant (P > 0.05), but MS-222 caused statistically quite high inhibition initially (P < 0.01). The inhibition effect of MS-222 diminished 1 h and 4 h after treatment (P < 0.05).