1-溴丙烷暴露生物标志物及对大鼠坐骨神经影响的研究

发布时间：2018-03-22 07:30

本文选题：1-溴丙烷　切入点：神经毒性　出处：《山西医科大学》2013年硕士论文　论文类型：学位论文

【摘要】：目的通过建立1-溴丙烷(1-BP)亚急性吸入染毒模型,研究1-BP对大鼠坐骨神经的毒性作用,并探寻反映1-BP对机体损害的指标；通过对1-BP暴露后大鼠尿样进行检测,寻找特异灵敏的1-BP接触标志物。方法 SPF级成年雄性Wistar大鼠48只按体重随机分为1-BP暴露低剂量组、中剂量组、高剂量组和对照组,每组12只。各组大鼠均置于动式吸入染毒柜内,分别给予设定剂量的1-BP1250mg/m3、2500mg/m3、5000mg/m3或新鲜空气,每天8小时,每周5天,连续4周。染毒以外时间将大鼠置于代谢笼中收集尿样。实验期间每三天称量一次大鼠体重。染毒结束次日将大鼠称重并用戊巴比妥钠麻醉后,用神经肌电仪测定大鼠坐骨神经的运动和感觉神经传导速度、末端潜伏期及波幅。之后每组取9只大鼠经腹主动脉采血处死,进行血常规和血生化检查。每组其余3只大鼠灌流固定后对坐骨神经进行病理学检查。采用气相色谱法对尿中3-溴丙酸进行测定,采用ICP-MS法对尿样进行总溴测定。结果 1.1-BP染毒期间暴露组大鼠逐渐出现食欲减退、活动减少和被毛稀疏凌乱等表现。染毒期间,低、中浓度染毒组大鼠体重呈增长趋势,但增长幅度小于对照组。高浓度组体重呈下降趋势,体重绝对值在染毒第1周后开始低于对照组(P0.05)。染毒3周后高浓度组大鼠后肢肌力明显下降。 2.神经电生理检查：各暴露组大鼠双侧运动神经传导速度均显著低于对照组(P0.01),运动神经末端潜伏期均较对照组延长(P0.05)。高浓度组双侧感觉神经传导速度均低于对照组(P0.05或P0.01),感觉神经末端潜伏期均较对照组延长(P0.05或P0.01),低、中浓度组感觉神经传导速度与对照组比较差异无统计学意义(P0.05)。各暴露组运动神经和感觉神经电刺激波幅与对照组相比均未见显著差异(P0.05)。 3.血常规检查：染毒结束时高浓度组大鼠的红细胞数和血红蛋白量均显著低于对照组(P0.05),所有染毒组大鼠红细胞平均体积(MCV)、平均血红蛋白量(MCH)和平均血小板体积(MPV)均显著高于对照组(P0.05)。血清生化检查：暴露组的AST、ALT值均显著高于对照组(P0.01),TP、IgG含量随暴露浓度增高而显著升高,CK、CP、IgM和钙离子随暴露浓度升高而呈降低趋势； 4.病理学检查显示高浓度组大鼠坐骨神经髓鞘疏松变性、排列杂乱,部分呈现空泡样变,轴索肿胀、偏移,间隙增宽。 5.尿中1-BP代谢物测定结果显示,各暴露组大鼠尿中总溴值均显著高于对照组。尿中总溴含量随着暴露时间的延长而逐渐升高,且和暴露浓度成正相关。尿中3-溴丙酸含量低于使用方法的检出限值。结论 1.1-BP暴露可引起大鼠坐骨神经传导速度的下降和末端潜伏期延长,运动神经比感觉神经损伤更敏感；还造成坐骨神经髓鞘和轴索的病理改变。坐骨神经的运动神经传导速度作为1-BP神经损伤的早期检测指标。 2. MCV、MCH、MPV和AST、ALT值的变化对1-BP暴露敏感,且呈现剂量反映关系,血清中TP、IgG、CK、CP、IgM和钙离子值也随1-BP暴露而发生显著变化,这些指标具有作为1-BP毒性作用生物标志物的可能性。 3.大鼠尿中总溴含量对1-BP暴露比较敏感,能够反映1-BP暴露情况,因此,尿中总溴值具有作为职业性1-BP接触的生物标志物的可能。
[Abstract]:Objective to establish a subacute inhalation exposure model of 1- bromine propane (1-BP), to study the toxic effects of 1-BP on sciatic nerve of rats, and to explore indicators that reflect the damage of 1-BP to rats, and to find specific and sensitive 1-BP contact markers by detecting urine samples after 1-BP exposure.
Method
SPF grade 48 adult Wistar male rats were randomly divided into 1-BP exposed to low dose group, middle dose group, high dose group and control group, 12 rats in each group. The rats were placed in a dynamic inhalation cabinet, set were given doses of 1-BP1250mg/m32500mg/m35000mg/m3 or fresh air, 8 hours a day, 5 a week day, for 4 weeks. The exposure time will collect samples outside the rats were placed in metabolic cages. During the experiment, every three days weighing a weight of rats. At the end of the next day the rats were weighed and anesthetized with pentobarbital sodium, determination of rat sciatic nerve motor and sensory nerve conduction velocity of nerve EMG. At the end of latency and amplitude. Then 9 rats from each group were sacrificed by abdominal aortic blood biochemical examination, blood routine and blood. The remaining 3 rats in each group rats perfused after pathological examination of the sciatic nerve. The urine by gas chromatography 3- bromine propionic acid was measured and total bromine was measured by ICP-MS method.
Result
1.1-BP exposure during exposure rats gradually diminished appetite, decreased activity and sparse coat messy performance. During the period of infection, low concentration of body weight in rats showed a rising trend, but the growth rate is less than the control group. High concentration group weight decreased, the absolute value of weight in rats after first weeks was lower than that of control group (P0.05). In the high concentration group of rat hindlimb muscle decreased significantly after 3 weeks.
2. electrophysiological examination: the exposure of bilateral motor nerve conduction velocity of rats were significantly lower than the control group (P0.01), motor nerve terminal latency was longer than the control group (P0.05). The high concentration group of bilateral sensory nerve conduction velocity was lower than the control group (P0.05 or P0.01), sensory nerve latency than the control group extended (P0.05 or P0.01), low concentration group, sensory nerve conduction velocity compared with the control group, the difference was not statistically significant (P0.05). The exposure group, motor nerve and sensory nerve stimulation wave amplitude compared with the control group showed no significant difference (P0.05).
3. blood routine examination: at the end of the experiment the number of red blood cells and hemoglobin content in high concentration group rats were significantly lower than the control group (P0.05), red blood cells of all rats were average volume (MCV), mean hemoglobin (MCH) and mean platelet volume (MPV) were significantly higher than the control group (P0.05). Serum biochemical examination: AST exposure group, ALT values were significantly higher than the control group (P0.01), TP, IgG content increased with the exposure concentration increased significantly, CK, CP, IgM and calcium ion concentration increased with the exposure decreased;
4. the pathological examination showed that the myelin sheath of the sciatic nerve was loose and denatured in the high concentration group and was arranged and disorderly. Some of the vacuolar changes were presented, and the axons were swollen, offset, and widened.
5. the 1-BP metabolites in urine showed that the total bromine value of urine in each exposure group was significantly higher than that in the control group. The total bromine content in urine increased gradually with the prolongation of exposure time, and positively correlated with the exposure concentration. The 3- bromine propionic acid content in urine was lower than the detection limit in use.
conclusion
1.1-BP exposure decreased the sciatic nerve conduction velocity and terminal latency, motor nerve is more sensitive than sensory nerve injury; also caused pathological changes of sciatic nerve myelin and axonal. Motor nerve conduction velocity of sciatic nerve as indicators of early detection of 1-BP nerve injury.
2. MCV, MCH, MPV and AST, ALT values were sensitive to 1-BP exposure, and showed a dose-response relationship. TP, IgG, CK, CP, IgM and Ca2 + values in serum also changed significantly with the exposure of the lungs. These indicators have the possibility of being a biomarker of toxic effects.
The total bromine content in 3. urine is more sensitive to 1-BP exposure, which can reflect 1-BP exposure. Therefore, the total bromine value in urine is a potential biomarker for occupational 1-BP exposure.

【学位授予单位】：山西医科大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R114

【参考文献】