游泳-水环境对大鼠海马活性氧、HPA轴激素影响探究摘要：目的：探索海马、下丘脑-垂体-肾上腺皮质（HPA）轴机能对训练及水环境的反应。方法：SD大鼠90%乳酸无氧阈强度负重游泳训练7周，大鼠力竭运动后即刻、力竭游泳后1小时及力竭游泳后1小时断头处死取样；另以不游泳大鼠浸水作为对照，每次浸水时间及最后取样时间与训练大鼠相一致。采用顺磁共振法测定海马軽自由基，放免法测定HPA轴激素。实验考虑了生物日节律的影响。结果：大鼠力竭后即刻下丘脑促肾上腺皮质激素释放激素（CRH）显著性高于浸水即刻；训练大鼠下丘脑皮质酮整体显著性高于浸水大鼠。力竭游泳后1小时海马轻自由基和下丘脑CRH显著性低于力竭后即刻和力竭后24小时；力竭后1小时血清皮质酮显著性高于力竭后24小时；浸水后1小时血清皮质酮也显著性高于浸水后24小时。下丘脑CRH和皮质酮受到游泳和浸水双重交互作用（p〈0.05）；另外，取样的日时间点与下丘脑CRH、血清和下丘脑皮质酮、海马務自由基有显著性相关，海马释自由基与血清皮质酮呈显著负相关。游泳和浸水干扰日节律与HPA轴激素的相关关系。结论：长期游泳训练在略低于无氧阈强度力竭运动，产生延迟性应激反应，水环境也产生类似的反应，可能是包括海马释自由基在内的海马信号的调节作用(但不仅限于餐自由基)；游泳训练及水环境在一定程度上干扰HPA轴激素的节律性分泌；游泳运动中水环境对时HPA轴激素的存在交互影响，水环境对HPA轴激素的分泌一定程度上被运动掩盖。关键词：运动；内分泌；氧化还原；环境；应激中图分类号：G804文献标识码：A文章编号：1004-4590(2008)01-0080-05^Abstract：AIM：Theaimofcurrentstudyistoresearchtheresponseoflongtimetrainingandimmersiononhippocampushydroxylradicalandhypothalamo-pituitary-adrenalaxishormones・Methods：Sprague-Dawleyratswereforcedswimmingburdenedwithatapproximately90%oftheweightcorrespondingtothelactateconcentrationthresholdfor7weeks.Sampleswereobtainedimmediately,lhrafterand24hrafteranexhaustiontestofgroupedrats,respectively.Incontrast,ratswerebarelyimmersedinwatercoincidedwithtimeofratsswimtraining,andalsocoincidedwithtimeofexecutionofswimtrainingratsafterthelastimmersion.Hydroxylradicalsinhippocampusweredeterminedwithelectronparamagneticresonancespectroscopy.Radioimmunoassayindetectthehormones・Rhythmofthedaytimewasconsidered・Double-blindmethodwasusedinthewholeresearch.Results：Corticotrophin-releasinghormone(CRH)inhypothalamusoftraininggrouprightafterexhaustionwassignificantlyhigherthantheimmersionratsatthesametime・Takentogetherofthewholethreetraininggroups,thecorticosteroneinhypothalamusweresignificantlyhigherthantheimmersionrats.ThehydroxylradicalinhippocampusandtheCRHinhypothalamusofthelhrafterexhaustionratsweresignificantlylowerthantheimmediateand24hrafterexhaustiongroups,respectively.Corticosteroneinbloodserumoftrainingratsatthelhrgroupweresignificantlyhigherthanthatof24hrgroup,andtheimmersionratsweresimilareither.Nosignificantdifferencesinallgroupsofadrenocorticotrophichormone(ACTH).ThereweresignificantinteractionbytheswimtrainingandimmersiontoCRHandcorticosteroneinhypothalamus・TherhythmofthedaytimehadsignificantcorrelationshipswithCRHinhypothalamus,corticosteroneinserumandhypothalamus,hydroxylradicalinhippocampus,respectively.Significantcorrelationshipalsoappearedbetweenhydroxylradicalinhippocampusandserumcorticosterone・Swimtrainingandimmersionpartlydisturbedthecorrelationshipsmentionedabove・Conclusion:ChronicswimmingtrainingattheintensityslightlybelowthelactateconcentrationthresholdmayinduceadelayedresponseoftheHPAaxishormonessecretiori.Thismayberegulatedbythehydroxylradicalsignal,butnottheonlyfactor.Swimt...