溴氰菊酯对大鼠脑中苄氧基试卤灵O-脱烷基化酶活力及CYP2B1/2B2蛋白水平的影响

Effect of deltamethrin on benzyloxyresorufin O-dealkylatase activity and CYP2B1/2B2 protein level in rat brain

目的 研究溴氰菊酯 (deltamethrin ,DM)对大鼠脑组织中苄氧基试卤灵O 脱烷基化酶(benzyloxyresorufinO dealkylatase,BROD)活力及CYP2B1 / 2B2蛋白水平的影响。方法 采用荧光分光光度法 ,在体内、体外研究了DM对大鼠脑组织中BROD活力的影响 ,并用Western blot法检测了DM对CYP2B1 / 2B2蛋白水平的影响。结果 大鼠连续 5d腹腔注射DM 1 2 .5mg·kg- 1 ·d- 1 染毒后 ,其全脑、大脑皮层及小脑BROD活力明显被抑制 ,其抑制率分别是 2 6 .7%、2 3 .8%和 33 .3 % ,差异均有显著性(P <0 .0 5) ;在体外 ,DM浓度在 2× 1 0 - 8～ 2× 1 0 - 4mol/L范围内对BROD活力无明显影响 ;DM在体内明显降低小脑中CYP2B1 / 2B2蛋白水平 ,其酶蛋白合成抑制率为 42 .6 %。结论 DM在体内能明显抑制脑内BROD活力 。

Objective To detect the effect of deltamethrin(DM) on benzyloxyresorufin O dealkylatase(BROD) activity and the expression of CYP2B1/2B2 in rat brain. Methods BROD activity was determined by flurophotometry under the treatment of DM in vivo and vitro.Western blot analysis was used to detect the expression of CYP2B1/2B2. Results In vivo,DM could markedly inhibit BROD activity in rat brain microsome after rats had been treated with DM (12.5 mg·kg -1 ·d -1 ,ip)for 5 days.The inhibitory rate in whole brain,cerebral cortex and cerebellum were 26.7%,23.8% and 33.3% respectively( P <0.05).However,in vitro,under the concentration of 2×10 -8 ～2×10 -4 mol/L of DM,there was no obvious change of BROD activity in rat brain.Moreover,Western blot analysis indicated that DM could significantly reduce the expression of CYP2B1/2B2 in vivo,the inhibitory rate of protein synthesis was 42.6%. Conclusion DM could inhibit BROD activity in rat brain and this effect may be related to the reduction of CYP2B1/2B2 protein synthesis.