Intervention effect of dimercaptopropansulfonate sodium on central toxic induced by bromoxynil in vivo

Objective To investigate the changes of γ-aminobutyric acid (GABA) and glutamate (Glu) in the cerebral cortex following acute bromoxynil intoxication in mice and the protective effect of sodium dimercaptopropane sulfonate (Na-DMPS). Methods 30 ICR mice were randomly divided into blank control group (10), exposure group (10) and Na-DMPS protection group (10). The levels of GABA and Glu in the cerebral cortex were measured by RP-HPLC. The glutamine (Gln) level and the glutamine synthetase (GS),glutamate decarboxylation enzyme (GAD), γ-aminobutyric acid transaminase (GABA-T) activity in the cerebral cortex were determined by U V colorimetric. Results Compared with the control group [GABA: (3.41 ±0. 12)μmol/g, Glu(14.00±0.16) μmol/g, Gln(1.25±0.19) μmol/g, GAD(13.50±0.25) μmol·g-1·h-1, GABA-T(25.51±0.21)μmol·g-1·h-1, GS( 142.19±1.31 ) U/mg pro], the level of GABA[(3.14±0. 14) μmol/g] was decreased (P＜0.05), whereas the level of Glu [(17.54±0.40) μmol/g] and Gln [(3.35±0.27) μmol/g] were increased (P＜0.05), the activity of GAD [( 11.93±0.15 ) μmol· g-1· h-1], GA BA-T[(24.15±0.22) μmol · g-1· h-1],GS [( 140.75±1.01 )U/mg pro] was decreased (P＜0.05) in acute intoxication group; Compared with the acute intoxication group, the level of GABA [(3.52±0.30) μmol/g] was increased (P＜0.05), whereas the level of Glu [( 14.20±0.32 ) μmol/g] and Gln [( 1.32±0.17 ) μmol/g] were decreased (P＜0.05), the activity of GAD [( 13.01 ±0.45 μmol ·g-1·h-1], GABA-T [(25.19±0.26) μmol·g-1 ·h-1, GS [(142.35±1.20) U/mg pro] was increased (P＜0.05 ) ;In contrast, the levels of GABA, Glu, Gln and the activity of GAD, GABA-T, and GS in Na-DMPS protection group were not significantly different in comparison with control group (P＞0.05). Conclusion The central toxic effects of mice with acute bromoxynil intoxication may be related to the changes of GABA and Glu content in the cerebral cortex;Na-DMPS can protect mice from bromoxynil-induced central toxic effects and GABA and Glu abnormal change in the cerebral cortex. Key words: Bromoxynil;  Acute toxicity tests;  Unithiol;  Cerebral cortex