肖衛(wèi)華,陳佩杰
IGF-1和MGF在過(guò)度訓(xùn)練抑制大鼠腹膜巨噬細(xì)胞吞噬功能中的作用研究
肖衛(wèi)華1,2,陳佩杰1
目的:觀察過(guò)度訓(xùn)練對(duì)大鼠腹膜巨噬細(xì)胞吞噬功能的影響及胰島素樣生長(zhǎng)因子1(IGF-1)和機(jī)械生長(zhǎng)因子(MGF)在其中所起的作用。方法:8周齡健康雄性Wistar大鼠16只,隨機(jī)分為安靜對(duì)照組(control)和過(guò)度訓(xùn)練組(overtraining)。過(guò)度訓(xùn)練組進(jìn)行11周遞增負(fù)荷跑臺(tái)訓(xùn)練。最后1次訓(xùn)練后36h,記錄體重變化并測(cè)定血液中血紅蛋白和睪酮含量。斷頭處死大鼠并分離純化腹膜巨噬細(xì)胞,中性紅法測(cè)定巨噬細(xì)胞吞噬功能,熒光定量PCR技術(shù)測(cè)定IGF-1和MGF基因表達(dá)。離體狀態(tài)下用不同濃度的IGF-1或MGF與巨噬細(xì)胞孵育2h,觀察IGF-1和MGF對(duì)巨噬細(xì)胞吞噬功能的影響。結(jié)果:與安靜對(duì)照組相比,過(guò)度訓(xùn)練組大鼠體重、血紅蛋白和睪酮含量均顯著降低,分別下降了約19.3%(P<0.01)、13.5%(P<0.01)、55.3%(P<0.01)。過(guò)度訓(xùn)練組巨噬細(xì)胞攝取中性紅能力顯著低于安靜對(duì)照組,下降約27%(P<0.05);過(guò)度訓(xùn)練組巨噬細(xì)胞IGF-1mRNA水平約為安靜對(duì)照組的21倍(P<0.01),MGF mRNA水平約為安靜對(duì)照組的92倍(P<0.01);IGF-1對(duì)巨噬細(xì)胞吞噬功能無(wú)顯著影響,各濃度組與未加藥組相比均無(wú)顯著性差異(P>0.05);MGF呈濃度依賴性的抑制巨噬細(xì)胞吞噬功能,與未加藥組相比,10ng/ml、50ng/ml組有顯著性差異(P<0.05),100ng/ml、200ng/ml組有極顯著性差異(P<0.01),各濃度組間比較無(wú)顯著性差異(P>0.05)。結(jié)論:過(guò)度訓(xùn)練抑制巨噬細(xì)胞吞噬功能;過(guò)度訓(xùn)練誘導(dǎo)產(chǎn)生的MGF可能在過(guò)度訓(xùn)練抑制巨噬細(xì)胞吞噬功能中發(fā)揮關(guān)鍵作用。
過(guò)度訓(xùn)練;巨噬細(xì)胞;吞噬功能;胰島素樣生長(zhǎng)因子1;機(jī)械生長(zhǎng)因子;鼠;動(dòng)物實(shí)驗(yàn)
規(guī)律性的身體活動(dòng)可以提高免疫機(jī)能,降低感染風(fēng)險(xiǎn);而長(zhǎng)時(shí)間、大強(qiáng)度運(yùn)動(dòng)則使感染幾率增加[16,22]。巨噬細(xì)胞在控制感染過(guò)程中發(fā)揮重要作用,是機(jī)體抵御病菌入侵的第一道防線。巨噬細(xì)胞廣泛分布于肺、肝、腎、腹腔、肌肉、血液等組織器官,具有吞噬、殺菌、抑制腫瘤、抗原遞呈、分泌炎性因子等多種功能[17]。吞噬作用是巨噬細(xì)胞最為重要的功能之一,可吞噬入侵的病菌及清除凋亡的機(jī)體細(xì)胞。有關(guān)運(yùn)動(dòng)與巨噬細(xì)胞吞噬功能的研究表明,長(zhǎng)期中低強(qiáng)度運(yùn)動(dòng)或短期劇烈運(yùn)動(dòng)均能提高巨噬細(xì)胞吞噬功能[8,9,23],但過(guò)度訓(xùn)練如何影響巨噬細(xì)胞吞噬功能未見(jiàn)相關(guān)研究。此外,運(yùn)動(dòng)影響巨噬細(xì)胞吞噬功能的相關(guān)機(jī)制鮮見(jiàn)報(bào)道。
研究表明,IGF-1能促進(jìn)巨噬細(xì)胞分泌TNF-α[21]和IL-1β[24]等炎性因子,促進(jìn)巨噬細(xì)胞攝取和降解低密度脂蛋白[13],誘導(dǎo)巨噬細(xì)胞向炎癥部位遷移參與炎癥反應(yīng)[10],調(diào)控巨噬細(xì)胞的分化和存活[19]等多種功能。但I(xiàn)GF-1是否參與巨噬細(xì)胞吞噬功能的調(diào)控,未見(jiàn)相關(guān)報(bào)道。此外,IGF-1前體選擇性剪接能產(chǎn)生多種異構(gòu)體,如IGF-1Ea、IGF-1Eb等,IGF-1Ea即為研究者常稱的IGF-1,IGF-1Eb在嚙齒類動(dòng)物中又被稱為“機(jī)械生長(zhǎng)因子”(mechano growth factor,MGF)[25]。MGF功能有別于IGF-1,具有增加肌肉體積和肌肉力量等多種功能,且MGF促進(jìn)肌肉體積增大的效應(yīng)遠(yuǎn)大于IGF-1[7]。此外,MGF可不通過(guò)IGF-1受體途徑發(fā)揮作用[26]。因此,MGF已經(jīng)成為了體育界的研究熱點(diǎn)[2,5,6]。安靜狀態(tài)下肌肉中IGF-1和MGF呈低豐度表達(dá),大強(qiáng)度運(yùn)動(dòng)可誘導(dǎo)其急劇增加[12]。報(bào)道顯示,巨噬細(xì)胞能表達(dá)IGF-1[10],但能否表達(dá)MGF及是否受大強(qiáng)度運(yùn)動(dòng)誘導(dǎo),未見(jiàn)相關(guān)報(bào)道。此外,MGF是否參與巨噬細(xì)胞功能調(diào)控,尚未見(jiàn)相關(guān)資料。
據(jù)此,本文提出如下假設(shè):過(guò)度訓(xùn)練可能通過(guò)抑制巨噬細(xì)胞吞噬功能從而降低免疫細(xì)胞功能,增加感染幾率;巨噬細(xì)胞中IGF-1和MGF表達(dá)可能與肌肉中相似,即在大強(qiáng)度運(yùn)動(dòng)誘導(dǎo)下表達(dá)量急劇增加,通過(guò)自分泌或旁分泌形式參與巨噬細(xì)胞吞噬功能的調(diào)控。為驗(yàn)證這一假設(shè),本文通過(guò)建立過(guò)度訓(xùn)練模型,以腹膜巨噬細(xì)胞為對(duì)象并結(jié)合離體實(shí)驗(yàn)展開(kāi)相關(guān)研究。
Wistar大鼠[中國(guó)科學(xué)院上海實(shí)驗(yàn)動(dòng)物中心/上海斯萊克實(shí)驗(yàn)動(dòng)物有限公司,SCXK(滬)2007-0005];RPMI1640,胎牛血清(GIBCO,美國(guó));青霉素-鏈霉素溶液(碧云天生物技術(shù)研究所);中性紅(Amersco,美國(guó));睪酮ELISA試劑盒(R&D Systems,美國(guó));Trizol(invitrogen,美國(guó));cDNA合成試劑盒,熒光定量PCR試劑盒(Fermentas,立陶宛);重組IGF-1(Sigma Aldrich,美國(guó));MGF多肽(上海吉爾生化有限公司);細(xì)胞培養(yǎng)板(Corning,美國(guó));其他試劑均為國(guó)產(chǎn)分析純。大鼠跑臺(tái)(DSPT-202跑臺(tái),杭州段氏制作公司);血細(xì)胞分析儀(Sysmex,日本);梯度PCR儀(Eppendorf,德國(guó));Rotor-Gene 3000熒光定量PCR儀(Corbett,澳大利亞);酶標(biāo)儀(Bio-Rad,美國(guó))。
1.2.1 實(shí)驗(yàn)動(dòng)物及分組
8周齡健康雄性Wistar大鼠16只,體重180±10g。動(dòng)物飼養(yǎng)環(huán)境溫度為22℃±2℃,相對(duì)濕度50%~70%,每天光照時(shí)間為12h,自由飲食。將大鼠隨機(jī)分為安靜對(duì)照組(control)和過(guò)度訓(xùn)練組(overtraining),每組8只。
1.2.2 過(guò)度訓(xùn)練方案
動(dòng)物適應(yīng)性飼養(yǎng)1周后,過(guò)度訓(xùn)練組開(kāi)始進(jìn)行遞增負(fù)荷的跑臺(tái)訓(xùn)練,每周6次,周日休息,共訓(xùn)練11周。過(guò)度訓(xùn)練方案參考文獻(xiàn)方法進(jìn)行[14](表1)。
1.2.3 過(guò)度訓(xùn)練模型驗(yàn)證
觀察大鼠精神狀況及運(yùn)動(dòng)能力的變化,且在最后1次訓(xùn)練后36h,記錄各組體重,并眼眶取血收集血液樣本。血細(xì)胞分析儀測(cè)定血紅蛋白含量。競(jìng)爭(zhēng)法ELISA測(cè)定血清睪酮含量,操作流程按產(chǎn)品說(shuō)明書(shū)。
1.2.4 腹膜巨噬細(xì)胞分離與純化
采用文獻(xiàn)方法[4,20]進(jìn)行并略作修改。眼眶取血后斷頭處死大鼠,腹腔注射12ml RPMI1640培養(yǎng)液,腹部按摩2 min后靜置5min,在腹部做約2cm長(zhǎng)開(kāi)口并小心吸取腹腔灌洗液入離心管。離心去上清,PBS洗2遍后用含10%胎牛血清的RPMI1640培養(yǎng)液重懸細(xì)胞并移入6孔板,于37℃、含5%CO2的培養(yǎng)箱中貼壁培養(yǎng)2h,傾去不貼壁細(xì)胞,貼壁細(xì)胞即為巨噬細(xì)胞,PBS(pH 7.4)輕柔洗滌2次后加入PBS小心吹打細(xì)胞入離心管,離心去上清后用RP-MI1640重懸細(xì)胞,用細(xì)胞計(jì)數(shù)板計(jì)數(shù),調(diào)濃度至2×106個(gè)/ml。
1.2.5 吞噬功能的測(cè)定
中性紅法測(cè)定巨噬細(xì)胞吞噬功能[15]。取100μl上述細(xì)胞懸液至96孔板,37℃、5%CO2的培養(yǎng)箱中孵育2h后,棄上清,加入200μl含0.1%中性紅溶液孵育30min,PBS洗3次后,加入無(wú)水乙醇和冰醋酸混合液(1∶1)200 μl并混勻,10min后于酶標(biāo)儀上測(cè)定550nm吸光度。吸光度即代表巨噬細(xì)胞吞噬功能。
表1 本研究過(guò)度運(yùn)動(dòng)方案一覽表Table 1 Overtraining Protocol
1.2.6 RNA抽提與cDNA合成
離心收集剩余的細(xì)胞。使用異硫氫酸胍-氯仿經(jīng)典法抽提總RNA。反轉(zhuǎn)錄反應(yīng)條件為:65℃,5min;4℃,2 min;25℃,5min;42℃,60min;70℃,5min。反應(yīng)總體積20μl,合成的cDNA儲(chǔ)存在-20℃?zhèn)溆茫?]。
1.2.7 熒光定量PCR
根據(jù)Genbank數(shù)據(jù)庫(kù)中公開(kāi)發(fā)表的基因序列,設(shè)計(jì)目的基因IGF-1和MGF及內(nèi)參基因β-actin的熒光定量引物(表2),引物由上海生工生物工程技術(shù)服務(wù)有限公司合成。雙標(biāo)曲法相對(duì)定量PCR,定量PCR反應(yīng)液包括:MaximaTMSYBR Green/ROX qPCR Master Mix(2×),12.5μl;上、下游引物各0.75μl(10μM);模板cDNA,1μl;DEPC水,10μl;總計(jì)25μl體積。反應(yīng)條件采用兩步法:50℃,2 min;95℃,10min;95℃(15s),60℃(60s),40個(gè)循環(huán)。IGF-1和MGF基因在1~105units范圍內(nèi),檢測(cè)閾值(CT)與拷貝數(shù)對(duì)數(shù)呈線性關(guān)系,兩者相關(guān)系數(shù)r>0.99。熔解曲線分析顯示二者均呈單一產(chǎn)物峰。
1.2.8 離體實(shí)驗(yàn)
取180g左右Wistar大鼠12只,按1.2.4所示分離純化腹膜巨噬細(xì)胞。所有純化的巨噬細(xì)胞混合重懸于無(wú)血清的RPMI1640中(含1%青霉素-鏈霉素溶液),調(diào)細(xì)胞濃度至2×106個(gè)/ml。取100μl至96孔板,無(wú)血清培養(yǎng)12 h后(排除血清干擾)[26],加入不同濃度的IGF-1或MGF溶液(終濃度0、1、10、50、100、200ng/ml),于37℃、5% CO2的培養(yǎng)箱中孵育2h后,按1.2.5所示測(cè)定巨噬細(xì)胞吞噬功能。每濃度3復(fù)孔,用不同的培養(yǎng)板重復(fù)3次。
表2 本研究熒光定量PCR引物一覽表Table 2 Primers Used for qRT-PCR
1.2.9 統(tǒng)計(jì)分析
實(shí)驗(yàn)數(shù)據(jù)用SPSS 17.0統(tǒng)計(jì)軟件處理,獨(dú)立樣本t檢驗(yàn)和單因素方差分析,統(tǒng)計(jì)學(xué)顯著性水平定為0.05。
2.1.1 一般觀察
前8周運(yùn)動(dòng)組大鼠狀態(tài)變化不明顯,不需過(guò)多外力協(xié)助即能較好的完成訓(xùn)練。隨著每天訓(xùn)練頻次的增加,即從第9周開(kāi)始至第11周,運(yùn)動(dòng)組大鼠精神狀態(tài)明顯下降,表現(xiàn)為毛發(fā)脫落、毛色晦暗、目光呆滯、易受驚嚇。同時(shí),運(yùn)動(dòng)能力下降,跟不上既定速度,需多次用手驅(qū)趕,協(xié)助其完成規(guī)定時(shí)間的運(yùn)動(dòng),運(yùn)動(dòng)后精疲力竭、喘息不止、趴地不起,且每天訓(xùn)練頻次越多,這一現(xiàn)象越明顯。
2.1.2 過(guò)度訓(xùn)練降低大鼠體重、血紅蛋白和睪酮含量
從表3可知,與安靜對(duì)照組相比,過(guò)度訓(xùn)練組大鼠體重、血紅蛋白和睪酮含量均顯著降低,分別下降了約19.3%(P<0.01)、13.5%(P<0.01)和55.3%(P<0.01)。
表3 本研究大鼠體重、血紅蛋白和睪酮含量變化一覽表Table 3 Body Weight,Hemoglobin,and Testosterone of Rats
過(guò)度訓(xùn)練組大鼠巨噬細(xì)胞攝取中性紅能力(0.27± 0.04)顯著低于安靜對(duì)照組(0.37±0.07),下降約27%,具有統(tǒng)計(jì)學(xué)意義(P<0.05)。
熒光定量PCR分析顯示,過(guò)度訓(xùn)練組大鼠巨噬細(xì)胞IGF-1mRNA水平約為安靜對(duì)照組的21倍(P<0.01);MGF mRNA水平約為安靜對(duì)照組的92倍(P<0.01)(圖1)。
圖1 過(guò)度訓(xùn)練對(duì)巨噬細(xì)胞IGF-1和MGF基因表達(dá)的影響示意圖Figure 1. Effect of Overtraining on IGF-1and MGF mRNA Level of Peritoneal Macrophages
純化的巨噬細(xì)胞經(jīng)12h無(wú)血清培養(yǎng)后,巨噬細(xì)胞與不同濃度IGF-1孵育2h,結(jié)果表明,IGF-1對(duì)巨噬細(xì)胞吞噬功能沒(méi)有顯著影響,各濃度組與未加藥組相比均無(wú)顯著性差異(P>0.05)。而巨噬細(xì)胞與不同濃度的MGF孵育2 h,巨噬細(xì)胞攝取中性紅的能力顯著降低,且呈濃度依賴性,10ng/ml、50ng/ml組與未加藥組相比有顯著性差異(P<0.05),100ng/ml、200ng/ml組與未加藥組相比有極顯著性差異(P<0.01),各濃度組間比較無(wú)顯著性差異(P>0.05)(圖2)。
競(jìng)技體育追求大強(qiáng)度的運(yùn)動(dòng)訓(xùn)練,運(yùn)動(dòng)員常處在過(guò)度訓(xùn)練的邊緣或已經(jīng)過(guò)度訓(xùn)練,這會(huì)對(duì)運(yùn)動(dòng)員運(yùn)動(dòng)成績(jī)的提高及身體健康造成嚴(yán)重影響,感染疾病的風(fēng)險(xiǎn)也隨之增加[22]。本研究通過(guò)長(zhǎng)時(shí)間、大強(qiáng)度運(yùn)動(dòng)模擬過(guò)度訓(xùn)練,觀察大鼠精神狀況及運(yùn)動(dòng)能力的變化,并監(jiān)測(cè)了反映過(guò)度訓(xùn)練的幾種常用指標(biāo)[1]。結(jié)果表明,在訓(xùn)練的后期,大鼠精神狀態(tài)及運(yùn)動(dòng)能力均降低。11周大強(qiáng)度運(yùn)動(dòng)使大鼠體重、血紅蛋白和睪酮含量均顯著降低(P<0.01),與安靜對(duì)照組相比分別下降了約19.3%、13.5%和55.3%,表明11周大強(qiáng)度運(yùn)動(dòng)誘導(dǎo)機(jī)體出現(xiàn)失衡狀態(tài),過(guò)度訓(xùn)練模型得以建立。本研究發(fā)現(xiàn),過(guò)度訓(xùn)練時(shí),巨噬細(xì)胞吞噬功能顯著低于安靜對(duì)照組大鼠,下降了約27%(P<0.05)。吞噬功能作為巨噬細(xì)胞最為重要的功能之一,過(guò)度訓(xùn)練引起吞噬功能降低勢(shì)必抑制其清除病菌的能力,這可能是過(guò)度訓(xùn)練增加感染風(fēng)險(xiǎn)的機(jī)制之一。
圖2 IGF-1和MGF對(duì)巨噬細(xì)胞吞噬功能的影響曲線圖Figure 2. Effect of IGF-1and MGF on the Phagocytosis of Peritoneal Macrophages
巨噬細(xì)胞能表達(dá)IGF-1,筆者推測(cè),巨噬細(xì)胞也能表達(dá)IGF-1的異構(gòu)體MGF并受大強(qiáng)度運(yùn)動(dòng)誘導(dǎo)。研究結(jié)果表明,11周大強(qiáng)度運(yùn)動(dòng)可誘導(dǎo)巨噬細(xì)胞中IGF-1和MGF基因表達(dá)急劇增加(分別增加約21倍和92倍)。巨噬細(xì)胞中MGF表達(dá)對(duì)運(yùn)動(dòng)應(yīng)激更敏感,這與肌肉中MGF表達(dá)對(duì)運(yùn)動(dòng)應(yīng)激更敏感的報(bào)道一致[12]。因 MGF具有不同于IGF-1的多種功能,其表達(dá)的差異可能具有重要生理意義。為探究過(guò)度訓(xùn)練狀態(tài)下巨噬細(xì)胞大量表達(dá)IGF-1和MGF的潛在意義,本研究采用離體方法觀察了不同濃度IGF-1或MGF對(duì)巨噬細(xì)胞吞噬功能的影響。結(jié)果發(fā)現(xiàn),各個(gè)濃度的IGF-1對(duì)巨噬細(xì)胞吞噬功能均無(wú)顯著影響,而MGF則呈濃度依賴性的抑制巨噬細(xì)胞吞噬功能。這提示,巨噬細(xì)胞中MGF可通過(guò)自分泌或旁分泌形式對(duì)巨噬細(xì)胞功能進(jìn)行調(diào)控。肌肉中MGF表達(dá)增加普遍被認(rèn)為是有益的,它可激活肌衛(wèi)星細(xì)胞,參與運(yùn)動(dòng)性肌肉肥大、損傷肌肉修復(fù)和防止肌肉萎縮[11,18]。但本研究中MGF可呈濃度依賴性的抑制巨噬細(xì)胞吞噬功能,表明MGF是巨噬細(xì)胞功能的負(fù)向調(diào)控因子。這些結(jié)果提示,過(guò)度訓(xùn)練時(shí)巨噬細(xì)胞中MGF呈高豐度表達(dá)具有重要生理意義,即MGF可能在抑制巨噬細(xì)胞吞噬功能中發(fā)揮關(guān)鍵作用。
本研究證明巨噬細(xì)胞可表達(dá)MGF且受大強(qiáng)度運(yùn)動(dòng)誘導(dǎo),且MGF參與了對(duì)巨噬細(xì)胞吞噬功能的調(diào)控,這可能是過(guò)度訓(xùn)練抑制免疫功能的新機(jī)制,但MGF抑制巨噬細(xì)胞吞噬功能的具體信號(hào)途徑仍有待深入研究。
過(guò)度訓(xùn)練抑制巨噬細(xì)胞吞噬功能;過(guò)度訓(xùn)練誘導(dǎo)產(chǎn)生的MGF可能在過(guò)度訓(xùn)練抑制巨噬細(xì)胞吞噬功能中發(fā)揮關(guān)鍵作用。
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Overtraining Inhibiting Phagocytosis of Rat Peritoneal Macrophages:Role of IGF-1and MGF
XIAO Wei-h(huán)ua1,2,CHEN Pei-jie1
Objective:To investigate the effects of overtraining on the phagocytosis of peritoneal macrophages and the roles of IGF-1and MGF in this process.Methods:16male wistar rats were randomized to 2groups:sedentary group(n=8)and overtraining group(n=8).Overtraining group was training in standard treadmill with an increasing load for 11weeks.36hafter the last session of exercise,record the body weight,blood was sampled at the retro-orbital sinus to determine the contents of hemoglobin and testosterone.Rats were sacrificed by decapitation,and then peritoneal macrophages were isolated and purified.The phagocytosis and mRNA levels of IGF-1and MGF were measured by the uptake of neutral red and real-time PCR respectively.In addition,we evaluate the effects of IGF-1and MGF peptide on phagocytosis of peritoneal macrophages in vitro(MФs were exposed to different concentrations of IGF-1or MGF peptide for 2h).Results:There was a decline of body weight(by 19.3%),hemoglobin(by 13.5%)and testosterone(by 55.3%)in overtraining group when compared with control group(P<0.01).Overtraining significantly inhibited phagocytosis of MФs(declined by 27%,P<0.05).When compared with the control group,IGF-1and MGF mRNA level in MФs from overtraining group increased 21-fold and 92fold,respectively(P<0.01).In vitro experiments showed that IGF-1had no significant effects on phagocytosis of MФs,there were no significant difference in each concentration when compared with untreated cells(P>0.05).Unlike IGF-1,MGF peptide impaired the phagocytosis of MФs in dose-independent manner.There were signifcant differences in 10ng/ml(P<0.05),50ng/ml(P<0.05),100ng/ml(P<0.01),200ng/ml(P<0.01),when compared with the untreated cells.There were no significant difference between different concentrations of MGF(P>0.05).Conclusion:These results suggest that overtraining inhibits the phagocytosis of peritoneal macrophages,and MGF produced by macrophages may play a key role in this process.
overtraining;macrophages;phagocytosis;insulin-likegrowthfactor-1;mecha-nogrowthfactor;rat;animalexperiment
G804.7
A
2011-07-06;
2011-09-11
國(guó)家自然科學(xué)基金資助項(xiàng)目(30971422);上海市重點(diǎn)學(xué)科建設(shè)資助項(xiàng)目(S30802);上海體育學(xué)院研究生創(chuàng)新基金(yjscx201004)。
肖衛(wèi)華(1981-),男,湖南安化人,講師,在讀博士研究生,研究方向?yàn)檫\(yùn)動(dòng)與健康促進(jìn),Tel:(021)51253242,E-mail:xiaoweihua1115@163.com;陳佩杰(1962-),男,浙江舟山人,教授,博士,博士研究生導(dǎo)師,研究方向?yàn)檫\(yùn)動(dòng)免疫學(xué)與青少年體質(zhì)研究,Tel:(021)51253626,E-mail:chengpjk@online.sh.cn。
1.上海體育學(xué)院運(yùn)動(dòng)科學(xué)學(xué)院,上海200438;2.湘南學(xué)院體育系,湖南郴州423000
1.College of Exercise and Sport Science,Shanghai University of Sport,Shanghai 200438,China;2.Department of Physical Education,Xiangnan University,Chenzhou 423000,China.
1000-677X(2011)10-0067-05