[摘要] 目的 觀察褪黑素對(duì)克山病病區(qū)低硒糧喂養(yǎng)的大鼠微觀結(jié)構(gòu)的影響。 方法 將SD大鼠分為3個(gè)組，分別用克山病病區(qū)低硒飼料、低硒飼料加硒、低硒飼料加褪黑素灌胃飼養(yǎng)，12周時(shí)檢查心肌及肝臟病理?yè)p傷情況。結(jié)果 12周時(shí)低硒組大鼠光鏡下見(jiàn)心肌局限性炎癥，電鏡下見(jiàn)心肌細(xì)胞線粒體明顯損傷。加硒組與褪黑素組心肌形態(tài)學(xué)檢查均未發(fā)現(xiàn)明顯的病變。12周時(shí)低硒組大鼠光鏡下肝臟病變檢出率明顯高于其他兩組。 結(jié)論 褪黑素可以預(yù)防低硒引起的大鼠心肌及肝臟的微觀結(jié)構(gòu)損傷，其保護(hù)作用可能與抗氧化機(jī)制有關(guān)。
[關(guān)鍵詞] 褪黑素；低硒；心肌損傷；肝臟損傷
Effects of melatonin on microstructure lesion of rats fed with lowselenium diet
WANG Hui,LIAN Minxue,ZHANG Chaoying,et al.Department of Geratology,the Second Hospital of Xian Jiaotong University,Xian 710004,China
[Abstract] Objective To observe the effects of melatonin on microstructure lesion of SpragueDawley rats caused by lowselenium diet of Keshan Disease area. Methods The rats were divided into three groups and fed with lowselenium diet of Keshan Disease area,seleniumsupplemented diet and lowselenium diet with melatonin(intragastric administration)respectively for twelve weeks,then myocardium lesion and liver lesion were examined in rats. Results Myocarditis under light microscope and mitochondrial damage under electron microscope can be found in the lowselenium group;Frequency of liver lesion occurred in lowselenium were significicantly higher than the other two groups(P<0.05). Conclusion Melatonin can protect microstructure of rats from damaging caused by lowselenium diet which might be related to an antioxidative mechanism.
[Key words] melatonin;low selenium;myocardium lesion;liver lesion
硒是谷胱甘肽過(guò)氧化物酶(GSH-Px)的活性中心，長(zhǎng)期缺硒可以導(dǎo)致脂質(zhì)過(guò)氧化代謝產(chǎn)物增加[1]，最終出現(xiàn)組織結(jié)構(gòu)和功能損害。動(dòng)物實(shí)驗(yàn)顯示，長(zhǎng)期食用克山病病區(qū)低硒糧會(huì)導(dǎo)致心肌氧化損傷[2]。具有較高水平酶活力的肝臟對(duì)低硒更為敏感，用低硒糧喂養(yǎng)大鼠，肝臟病變的檢出率高于心肌病變檢出率[3]。補(bǔ)硒可以預(yù)防克山病病區(qū)低硒糧引起的心肌及肝臟損傷，但由于硒的生物學(xué)效應(yīng)具有雙向性，若補(bǔ)硒過(guò)量則非但不能起到提高機(jī)體抗氧化功能的作用，反而會(huì)使機(jī)體的脂質(zhì)過(guò)氧化反應(yīng)增強(qiáng)[4]，因此，研究其他具有抗氧化作用的物質(zhì)對(duì)低硒所致機(jī)體氧化損傷的影響，具有重要意義。
褪黑素(melatonin，MT)是松果體合成與分泌的神經(jīng)內(nèi)分泌激素。近10年來(lái)褪黑素的抗氧化作用[5，6]已經(jīng)引起人們的普遍關(guān)注，本實(shí)驗(yàn)的目的在于：研究褪黑素能否預(yù)防克山病病區(qū)低硒糧引起的大鼠心肌及肝臟的微觀結(jié)構(gòu)損傷。
[關(guān)鍵詞] 褪黑素；低硒；心肌損傷；肝臟損傷
Effects of melatonin on microstructure lesion of rats fed with lowselenium diet
WANG Hui,LIAN Minxue,ZHANG Chaoying,et al.Department of Geratology,the Second Hospital of Xian Jiaotong University,Xian 710004,China
[Abstract] Objective To observe the effects of melatonin on microstructure lesion of SpragueDawley rats caused by lowselenium diet of Keshan Disease area. Methods The rats were divided into three groups and fed with lowselenium diet of Keshan Disease area,seleniumsupplemented diet and lowselenium diet with melatonin(intragastric administration)respectively for twelve weeks,then myocardium lesion and liver lesion were examined in rats. Results Myocarditis under light microscope and mitochondrial damage under electron microscope can be found in the lowselenium group;Frequency of liver lesion occurred in lowselenium were significicantly higher than the other two groups(P<0.05). Conclusion Melatonin can protect microstructure of rats from damaging caused by lowselenium diet which might be related to an antioxidative mechanism.
[Key words] melatonin;low selenium;myocardium lesion;liver lesion
硒是谷胱甘肽過(guò)氧化物酶(GSH-Px)的活性中心，長(zhǎng)期缺硒可以導(dǎo)致脂質(zhì)過(guò)氧化代謝產(chǎn)物增加[1]，最終出現(xiàn)組織結(jié)構(gòu)和功能損害。動(dòng)物實(shí)驗(yàn)顯示，長(zhǎng)期食用克山病病區(qū)低硒糧會(huì)導(dǎo)致心肌氧化損傷[2]。具有較高水平酶活力的肝臟對(duì)低硒更為敏感，用低硒糧喂養(yǎng)大鼠，肝臟病變的檢出率高于心肌病變檢出率[3]。補(bǔ)硒可以預(yù)防克山病病區(qū)低硒糧引起的心肌及肝臟損傷，但由于硒的生物學(xué)效應(yīng)具有雙向性，若補(bǔ)硒過(guò)量則非但不能起到提高機(jī)體抗氧化功能的作用，反而會(huì)使機(jī)體的脂質(zhì)過(guò)氧化反應(yīng)增強(qiáng)[4]，因此，研究其他具有抗氧化作用的物質(zhì)對(duì)低硒所致機(jī)體氧化損傷的影響，具有重要意義。
褪黑素(melatonin，MT)是松果體合成與分泌的神經(jīng)內(nèi)分泌激素。近10年來(lái)褪黑素的抗氧化作用[5，6]已經(jīng)引起人們的普遍關(guān)注，本實(shí)驗(yàn)的目的在于：研究褪黑素能否預(yù)防克山病病區(qū)低硒糧引起的大鼠心肌及肝臟的微觀結(jié)構(gòu)損傷。