有氧运动对染毒马拉硫磷大鼠肠神经毒效应的影响

Effect of aerobic exercise on enteric nervous injury in rats exposed to malathion

目的探讨有氧运动对有机磷农药马拉硫磷染毒大鼠肠神经毒效应的影响。方法成年雄性Wistar大鼠进行无负重游泳,隔天1次,每周3次,每次1 h,持续6周;运动前ig给予马拉硫磷染毒100 mg·kg-1·d-1,每周6 d,持续6周。测定血清乙酰胆碱酯酶(AChE)和丁酰胆碱酯酶(BuChE)活性,测定小肠推进指数;观察回肠神经丛分布,免疫组化法测定回肠蛋白基因相关肽9.5(PGP9.5)、P物质(SP)和血管活性肠肽(VIP)的表达水平。结果与正常对照组相比,马拉硫磷染毒组大鼠AChE和BuChE活性显著下降(P<0.01),小肠推进指数显著升高,回肠PGP9.5水平显著下降,SP水平显著升高,VIP水平显著下降(P<0.05);有氧运动组胆碱酯酶活性无变化,小肠推进指数显著降低,回肠PGP9.5水平显著升高,SP水平显著降低,VIP水平显著升高。与单纯马拉硫磷染毒组相比,染毒运动组大鼠胆碱酯酶活性显著下降(P<0.01),小肠推进指数由染毒组(89±4)%降至(79±5)%(P<0.01),回肠PGP9.5水平由染毒组0.012±0.003升至0.029±0.015(P<0.01),SP水平由染毒组0.174±0.067降至0.110±0.057(P<0.05),VIP水平由染毒组0.0076±0.0029升至0.0111±0.0047(P<0.05),恢复至或接近正常对照组水平。结论马拉硫磷染毒干扰大鼠肠神经系统的功能,有氧运动改善马拉硫磷染毒对大鼠的肠神经毒效应,但不改善染毒对血清胆碱酯酶活性的抑制。

OBJECTIVE To investigate the effects of aerobic exercise on enteric nervous injury in rats exposed to malathion.METHODS Adult male Wistar rats were treated with non-load swi mming every other day,three ti mes a week,each one hour,for six weeks.Before exercise,the rats were trea-ted with malathion 100 mg·kg -1·d -1 by oral gavage,six days a week,for six weeks.The activities of seru m acetylcholinesterase（AChE）and butyrocholinesterase（BuChE）were determined.In addition,the s mall intestinal propulsion indexes were measured.Also,the distribution of nerve plexus in ileu m was observed.The i mmunohistoche mical method was used to measure the levels of protein gene-related petide 9.5 （PGP9.5）,substance P （SP）,and vasoactive intestinal peptide （VIP）.RESULTS Co m-pared with normal control,malathion exposure decreased the activities of seru m AChE and BuChE （P〈0.01 ）,increased the s mall intestinal propulsion indexes （P 〈0.05）.In addition,the levels of PGP9.5 decreased （P〈0.05）.At the sa me ti me,the levels of SP increased,and the levels of VIP decreased （P〈0.05）.Aerobic exercise did not change the activites of cholinesterases,but decreased s mall intes-tinal propulsion indexes,increased the levels of PGP9.5,decreased the levels of SP,and increased the levels of VIP.Co mpared with the malathion exposure only,the rats in malathion ad ministration co mbined with aerobic exercise group de monstrated much lower activites of cholinesterase （P 〈0.01 ）,and the s mall intestinal propulsion indexes decreased fro m （89 ±4）% to （79 ±5）%（P 〈0.01 ）.Moreover,the levels of PGP9.5 increased fro m 0.012 ±0.003 to 0.029 ±0.015 （P 〈0.01 ）.At the sa me ti me,the levels of SP decreased fro m0.174 ±0.067 to 0.1 10 ±0.057（P〈0.05）,and the levels of VIP increased fro m 0.0076 ±0.0029 to 0.01 1 1 ±0.0047 （P 〈0.05）.The levels of above para meters were sa me or close to those of the normal control.CONCLUSION Malathion exposure induced disorders of enteric nervous syste m in rats,and the aerobic exercise abated the toxic response in enteric nervous syste m of malathion exposure rats.However,these effects were not mediated through recovery of cholinesterases inhibition.