【摘要】 目的探讨磺草酮(一种三酮类除草剂)亚慢性暴露对大鼠糖代谢和酪氨酸代谢的影响。方法以不同剂量磺草酮(5、505、00 mg/(kg.d))混饲染毒90 d。分别测定第零天、306、0、90 d空腹血糖;实验结束后行糖耐量试验;并检测肝脏4-羟苯丙酮酸二加氧酶(HPPD)活力及血清酪氨酸、肾上腺素含量。结果染毒组大鼠各时间点空腹血糖,糖耐量及血清肾上腺素水平与对照组相比,其差异均无统计学意义;染毒组大鼠肝脏HPPD活力与对照组相比均明显下降(P<0.001);染毒组大鼠血清酪氨酸水平与对照组相比均明显升高(P<0.001),且酪氨酸水平有随染毒剂量增高而升高的趋势。结论磺草酮有效抑制大鼠肝脏HPPD活力,干扰大鼠酪氨酸代谢,诱发严重酪氨酸血症。尽管酪氨酸还是肾上腺素等儿茶酚胺类激素的前提物质,但在本实验中未发现大鼠肾上腺素发生显著性改变,同时也未见糖代谢异常。更多还原

【Abstract】 Objective To investigate the effect of subchronic exposure to sulcotrione,a member of the triketone class of herbicides,on glucose and tyrosine catabolism in the rat.Methods Sulcotrione was administered through food at does of 5,50,500 mg/kg·d for 90 d.During treatment we measured fasting blood glucose in 0,30,60,90 d.At the end of the experiment,oral glucose tolerance test(OGTT) was adopted,and the activities of hepatic 4-Hydroxyphenylpyruvate dioxygenase(HPPD) in the homogenate,serum tyrosine and epinephrine were analyzed. Results Sulcotrione at all doses,had no significant effects on fasting blood glucose,glucose tolerance and serum epinephrine of control,respectively.While sulcotrione significantly decreased hepatic HPPD activity(P<0.001),and markedly increased serum tyrosine(P<0.001) at all doses compared to control,The tyrosinemia being does-dependent.Conclusion Sulcotrione potent inhibits hepatic HPPD,altering tyrosine catabolism,and causes severe tyrosinemia.Although tyrosine is precursor of catecholamine,there is no significant effect on serum epinephrine concentration and glucose homeostasis.更多还原