SARS患者尸检肺组织的TGF-β检测

为了研究TGFβ1在严重急性呼吸综合征(Severeacuterespiratorysyndrome,SARS)尸检肺组织中的表达情况及其在患者肺组织损伤中的可能作用,对2例SARS尸检肺组织进行病理学观察;应用免疫组化方法检测TGFβ1在尸检肺组织及对照肺组织中的表达情况,并进行半定量分析。结果显示病例一尸检肺组织主要病理改变为弥漫性肺泡损伤,透明膜形成及渗出性炎症。病例二尸检肺组织除了上述改变外,还伴有肺泡间质纤维增生和肺泡早期纤维化等机化性肺炎改变。TGFβ1平均灰度值在SARS患者肺组织为103.43±0.62;小叶性肺炎组织为131.47±2.64;正常肺组织中为144.24±0.09。3组比较有显著差别(P值<0.05)。SARS病毒感染后可引起急性肺间质和肺泡渗出性炎症,中后期病例还伴有肺泡间质纤维增生和肺泡早期纤维化;SARS患者肺组织损伤及纤维化与SARS冠状病毒感染后TGFβ1表达增强有关,提示抗TGFβ1治疗在SARS患者肺损伤、纤维化的预防、治疗过程中可能具有一定的临床意义。     

放射性肺损伤细胞渗出及SP-A表达的实验研究

目的探讨急性放射性肺损伤不同时间点病理和肺泡灌洗液与肺泡表面活性蛋白A(SP-A)表达的变化。方法健康雄性Wistar大鼠40只随机分为对照组(C组)和照射组(R组)。行6MV-X线全胸野照射,剂量率2Gy/min,单次剂量15Gy,源皮距1m,照射面积4.5cm×4.5cm。于照射后第1,2,4,8周取肺组织作HE、Masson染色,肺泡灌洗液进行细胞计数,蛋白免疫印迹(Westernblot)检测肺组织中SP-A蛋白表达。结果HE和Masson染色提示照射后的第1周始肺泡腔有炎性细胞渗出,继之间质水肿,第4及8周出现肺泡腔变小甚至结构破坏,局部实变,肺间质出现胶原纤维;肺泡灌洗液的细胞总数照射组与对照组相比各时间段都明显增高(P<0.01);照射组各时间点SP-A蛋白表达均明显下降(P<0.001),以第1、8周下降最为明显,第2、4周出现回升。结论SP-A蛋白参与放射性肺损伤的发生、发展过程,为进一步探讨放射性肺损伤的发病机制提供了实验依据。     

当归对高脂血清所致ECV304细胞损伤的保护作用

实验观察了高脂血清对培养的人脐静脉内皮细胞（ECV304）的损伤及传统中药当归的保护作用,以探讨当归的抗动脉粥样硬化作用及其可能机制,培养人脐静脉内皮细胞,以高脂血清作损伤因子,用扫描电镜观察细胞的超微结构,分光光度法检测细胞培养液中一氧化氮（NO）的含量,免疫细胞化学方法检测细胞表面细胞间粘附分子－1（ICAM－1）,碱性成纤维细胞生长因子（bFGF)及转化生长因子β1（TGFβ）的表达,与高脂血清孵育24h后,内皮细胞的超微结构明显收损,且细胞表面ICAM－1,bFGF的表达明显增加,而细胞培养液中NO的量及细胞表达TGFβ1明显减少,加入当归后,高脂血清对内皮细胞的这些作用均可被逆转,当归对内皮细胞中ICAM－1,bFGF,TGFβ及NO表达改变的影响可能与其抗动脉粥样硬化的作用有关。     

急性放射性肝损伤大鼠模型的建立与评价

目的探讨急性放射性肝损伤大鼠模型的建立及TGF-β1动态变化的意义。方法选用雄性SD大鼠40只,随机分为模型组(30只)和对照组(10只)。除对照组外,模型组大鼠右半肝均接受单次6 MV X线25 Gy照射,接受照射第3、5、10天,应用HE染色、透射电镜下观察大鼠右肝病理学变化,血清学检测TGF-β1、肝功能相关指标(ALT,AST,ALP),数据用SPSS 17.0统计软件进行分析。结果在照射第3、5、10天后,电镜下可观察肝脏早期病理学改变;TGF-β1的表达随时间延长而逐渐增加,模型组与对照组比较、不同时间段相比较,差异均有统计学意义(P0.05);对照组和模型组的HE染色结果之间无明显差别;肝功能相关指标(ALT,AST,ALP)不同时间点比较无明显统计学意义(P0.05)。结论电镜下观察肝脏病理学改变早于光镜下的变化,可用于早期放射性肝损伤的评价;TGF-β1较肝功能更加敏感地反映出照射后肝脏的损伤状态,可作为预测急性放射性肝损伤程度的血清细胞因子。     

大鼠放射性肺损伤模型的建立与动态观察

目的：建立并鉴定大鼠放射性肺损伤模型,摸索大鼠放射性肺损伤的病理变化规律,阐明氧化应激在其发生发展过程中的作用。方法：采用60Co源22Gy单次照射SD大鼠全肺。分别于照射前、照后1天,7天,15天,21天,30天,60天,120天活杀大鼠,计算肺系数,右肺行HE染色、Masson染色及天狼猩红染色,观察肺组织病理变化并对大鼠肺泡炎及纤维化程度进行评分,免疫组化法检测肺组织廿SMA表达情况;左肺进行羟脯氨酸含量测定;血清测定MDA含量、总SOD活力和TGF-β1含量。结果：（1）大鼠肺脏于照后15天开始出现明显大体改变,病理学表现为间质性渗出性炎症并随时间延长逐渐加重,照后60天至120天肺脏塌陷,表面可见纤维化病灶,病理改变以肺间隔内细胞增生和胶原纤维沉积为主;（2）血清T-SOD活力照后1天至7天短暂增加后其活力持续降低;血清MDA含量和TGF-β1含量随时间时间延长逐渐增高;（3）照后60天肺组织a-SMA表达明显增加,至照后120天最为显著。结论：成功建立了大鼠放射性肺损伤模型并阐述了其病理变化规律;氧化应激参与了放射性肺损伤的病理过程。为其防治提供了实验基础和理论依据。     

SARS患者尸检肺组织的TGF-β检测

为了研究TGF-β1在严重急性呼吸综合征(Severe acute respiratory syndrome, SARS)尸检肺组织中的表达情况及其在患者肺组织损伤中的可能作用,对2例SARS尸检肺组织进行病理学观察;应用免疫组化方法检测TGF-β1在尸检肺组织及对照肺组织中的表达情况,并进行半定量分析. 结果显示病例一尸检肺组织主要病理改变为弥漫性肺泡损伤,透明膜形成及渗出性炎症.病例二尸检肺组织除了上述改变外,还伴有肺泡间质纤维增生和肺泡早期纤维化等机化性肺炎改变.TGF-β1平均灰度值在SARS患者肺组织为103.43±0.62;小叶性肺炎组织为131.47±2.64;正常肺组织中为144.24±0.09.3组比较有显著差别(P值＜0.05).SARS病毒感染后可引起急性肺间质和肺泡渗出性炎症,中后期病例还伴有肺泡间质纤维增生和肺泡早期纤维化;SARS患者肺组织损伤及纤维化与SARS冠状病毒感染后TGF-β1表达增强有关,提示抗TGF-β1治疗在SARS患者肺损伤、纤维化的预防、治疗过程中可能具有一定的临床意义.     

原儿茶酸对脂多糖诱导的急性肺损伤小鼠的保护作用

目的:探索原儿茶酸(protocatechuicacid,PCA)对脂多糖(lipopolysaccharide,LPS)诱导的急性肺损伤(acute lung injury,ALI)小鼠的保护作用,探讨其保护机制。方法:将40只昆明小鼠按随机数字表法均分为空白对照组(NC组)、LPS模型组、原儿茶酸预处理组(PCA+LPS组)、地塞米松阳性对照组(Dex+LPS组),每组10只,模型组以5mg·kg-1脂多糖腹腔内注射诱导急性肺损伤。6h后处死小鼠,HE染色观察肺组织病理学变化;BCA法检测肺泡灌洗液中总蛋白浓度;ELISA检测肺泡灌洗液炎症因子TNF-α、IL-1β含量;Western Blot检测肺组织中p38MAPK、p-p38MAPK、p-ATF2蛋白的表达水平。结果:与对照组相比,模型组小鼠肺损伤明显,肺泡内出血、水肿、炎细胞浸润,肺泡灌洗液中TNF-α、IL-1β的含量及总蛋白浓度增加,肺组织中p38MAPK/p-p38MAPK、p-ATF2表达均明显增加(均P0.01)。与模型组相比,原儿茶酸预处理组、地塞米松阳性对照组肺组织病理损伤程度明显减轻,肺泡灌洗液中TNF-α、IL-1β的含量及总蛋白浓度、肺组织中p38MAPK/p-p38MAPK、p-ATF2表达均明显降低(均P0.01)。结论:PCA对LPS诱导的急性肺损伤有保护作用,其作用机制可能与其抑制p38MAPK-p-ATF2信号通路的活化、降低肺组织炎症反应有关。     

Wnt/beta-catenin信号通路关键因子在放射性肺纤维化中的作用

目的：观察直线加速器X射线照射对人肺成纤维细胞(HLFs)Wnt/beta-catenin 信号通路关键信号因子的影响并探讨其意义。方 法：HLFs分别经直线加速器0Gy、5Gy、8Gy X线照射后,MTT 比色法检测其增殖活性,筛选合适照射剂量。人肺成纤维细胞分为 照射组(R 组)和正常对照组(C 组),R 组经直线加速器X射线,5 Gy 照射24 h后,免疫荧光检测成纤维细胞alpha-SMA表达,Western blot检测成纤维细胞中GSK-3beta、p-GSK-3beta表达。结果：X 线5 Gy照射剂量可使人肺成纤维细胞增殖活力增强,较0 Gy、8 Gy增 殖曲线明显。照射组人肺成纤维细胞形态较正常组有明显差异。照射组人肺成纤维细胞琢-SMA,p-GSK-3beta表达水平升高, p-GSK-3beta/GSK-3beta比值升高,与正常对照组比较均有统计学意义(P<0.05)。结论：Wnt/beta-catenin 信号通路在放射性肺损伤的发生 发展中起调控作用,可能为放射性肺纤维化的治疗提供了新视角。     

LPS诱导的急性肺损伤中早期标志物表达研究

目的探讨长链非编码RNA在内毒素诱导的急性肺损伤早期表达。方法应用脂多糖(Lipopolysacharide,LPS)在健康昆明小鼠气管内滴注建立急性肺损伤动物模型;查找文献,筛选小鼠肺组织在炎症后差异表达的lnc RNAs,选取部分lnc RNAs(LncRNA IL-7R、LncRNA H19、LncRNAHotair、LncRNA Maltal1、LncRNA acta-1、LncRNA Cot2)进行实时荧光定量PCR验证和生物信息学分析,验证可能与LPS诱导的急性肺损伤发生相关的lnc RNAs表达的变化,及其与LPS诱导急性肺损伤主要信号通路TLR4-MYD88-NF-kb P65通路的相关成员的变化水平,为其在急性肺损伤发生中的机制研究提供前期基础。结果气道内直接滴入LPS 24h后,TLR4、MYD88、LncRNAH19在LPS诱导的急性肺损伤小鼠模型的肺组织中,实验组较对照组的基因表达水平增高(P0.05);LncRNA IL-7R、LncRNAHotair、LncRNA Maltal1、LncRNA acta-1、LncRNA Cox2基因水平的表达,两组比较无明显差异性(P0.05)。经地塞米松干预后,在急性肺损伤炎症小鼠肺组织中,干预组TLR4、DYD88、LncRNA H19的基因表达水平均较实验组出现不同程度降低(P0.05)。结论 LncRNA H19、LncRNA IL-7R可能通过信号通路TLR4-MYD88-NF-kb P65参与内毒素诱导的急性肺损伤中早期表达,但其与肺损伤的关系有待进一步研究。     

葛根素对脂多糖导致的大鼠急性肺损伤组织中水通道蛋白-1的影响

目的:观察葛根素对脂多糖诱导的急性肺损伤大鼠肺组织水通道蛋白-1(AQP1)表达、病理形态学、湿干比等的影响,探讨其对急性肺损伤的保护作用.方法:健康Wistar大鼠36只,采用腹腔内注射脂多糖(lipopolysaccharide,LPS)法复制急性肺损伤动物模型.将大鼠随机分为盐酸对照组(对照组)、LPS损伤组(损伤组)和葛根素+LPS组(葛根素组).结果:光镜下见对照组肺泡结构清晰,肺泡腔及支气管腔未见明显炎细胞及渗出物.LPS组镜下可见肺组织水肿,表面可见暗红色点、片状出血,大量炎性细胞浸润,肺泡间隔明显增厚,葛根素+LPS组损伤较LPS组明显减轻.LPS组湿干比较对照组增高,葛根素组湿干比较LPS组降低.LPS组AQP1蛋白表达较对照组减少,葛根素组肺组织AQP1蛋白表达较LPS组明显增加.结论:葛根素对脂多糖所致的大鼠急性肺损伤具有保护作用.     

Lung tissue extracellular matrix-derived hydrogels protect against radiation-induced lung injury by suppressing epithelial–mesenchymal transition

This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage.     

Effects of ionizing radiation and beta-adrenergic stimulation on the expression of early response genes in rat parotid glands.

There is little known about the regulation of gene expression in rat parotid glands after exposure to ionizing radiation. The present studies investigate the effects of in vivo ionizing radiation, with subsequent stimulation of beta-adrenergic receptors by isoproterenol, on parotid gland function and on the expression of the early response genes, c-fos, c-jun, and jun B. Ionizing radiation diminished parotid gland weight and saliva output. Treatment of irradiated rats with isoproterenol increased the gland weight to levels similar to those in nonirradiated rats. However, such treatment had no effect on saliva output as indicated by measurements of parotid salivary flow rate. Irradiation alone increased the expression of c-fos, c-jun, and jun B. The combination of irradiation and isoproterenol had an additional effect on the levels of c-fos and jun B mRNAs and proteins particularly at earlier experimental times (1 to 8 h). Isoproterenol alone induced high levels of c-fos and jun B mRNA but not of c-jun mRNA. However, c-jun mRNA was induced markedly by radiation and 8 h of isoproterenol treatment, indicating a combined effect on c-jun gene expression. These observations suggest that the expression of the proto-oncogenes c-fos, c-jun, and jun B is probably regulated through differential signal transduction pathways which may be activated by these external stimuli and may be associated with functional changes induced in the rat parotid gland by ionizing radiation and by ionizing radiation and isoproterenol.     

Diagnosis of Partial Body Radiation Exposure in Mice Using Peripheral Blood Gene Expression Profiles

In the event of a terrorist-mediated attack in the United States using radiological or improvised nuclear weapons, it is expected that hundreds of thousands of people could be exposed to life-threatening levels of ionizing radiation. We have recently shown that genome-wide expression analysis of the peripheral blood (PB) can generate gene expression profiles that can predict radiation exposure and distinguish the dose level of exposure following total body irradiation (TBI). However, in the event a radiation-mass casualty scenario, many victims will have heterogeneous exposure due to partial shielding and it is unknown whether PB gene expression profiles would be useful in predicting the status of partially irradiated individuals. Here, we identified gene expression profiles in the PB that were characteristic of anterior hemibody-, posterior hemibody- and single limb-irradiation at 0.5 Gy, 2 Gy and 10 Gy in C57Bl6 mice. These PB signatures predicted the radiation status of partially irradiated mice with a high level of accuracy (range 79–100%) compared to non-irradiated mice. Interestingly, PB signatures of partial body irradiation were poorly predictive of radiation status by site of injury (range 16–43%), suggesting that the PB molecular response to partial body irradiation was anatomic site specific. Importantly, PB gene signatures generated from TBI-treated mice failed completely to predict the radiation status of partially irradiated animals or non-irradiated controls. These data demonstrate that partial body irradiation, even to a single limb, generates a characteristic PB signature of radiation injury and thus may necessitate the use of multiple signatures, both partial body and total body, to accurately assess the status of an individual exposed to radiation.     

Temporal expression of hypoxia-regulated genes is associated with early changes in redox status in irradiated lung

The development of normal lung tissue toxicity after radiation exposure results from multiple changes in cell signaling and communication initiated at the time of the ionizing event. The onset of gross pulmonary injury is preceded by tissue hypoxia and chronic oxidative stress. We have previously shown that development of debilitating lung injury can be mitigated or prevented by administration of AEOL10150, a potent catalytic antioxidant, 24h after radiation. This suggests that hypoxia-mediated signaling pathways may play a role in late radiation injury, but the exact mechanism remains unclear. The purpose of this study was to evaluate changes in the temporal expression of hypoxia-associated genes in irradiated mouse lung and determine whether AEOL10150 alters expression of these genes. A focused oligo array was used to establish a hypoxia-associated gene expression signature for lung tissue from sham-irradiated or irradiated mice treated with or without AEOL10150. Results were further verified by RT-PCR. Forty-four genes associated with metabolism, cell growth, apoptosis, inflammation, oxidative stress, and extracellular matrix synthesis were upregulated after radiation. Elevated expression of 31 of these genes was attenuated in animals treated with AEOL10150, suggesting that expression of a number of hypoxia-associated genes is regulated by early development of oxidative stress after radiation. Genes identified herein could provide insight into the role of hypoxic signaling in radiation lung injury, suggesting novel therapeutic targets, as well as clues to the mechanism by which AEOL10150 confers pulmonary radioprotection.     

旋转磁场对^60Coγ射线放射损伤小鼠肺损伤影响

目的：探讨旋转磁场对放射损伤小鼠肺损伤的影响。方法：132只雄性BALB／c小鼠随机分为正常组（N）,单纯磁疗组（M）,单纯照射组（R）和照射磁疗组（IHM）4组,R组和R＋M组小鼠接受吸收剂量6．0Gy的^60Coγ射线全身一次照射,M组及N组不予以照射,M组及R＋M组予以磁场处理30d,每天2次,每次1．5h,分别于第9,23、30d测定小鼠湿肺羟脯氨酸含量,并进行小鼠肺光镜、电镜超微结构的观察。结果：N组和M组肺羟脯氨酸含量在3个时间点上都低于R组和R＋M组,有明显差别（P均〈0．05）。R组和R＋M组肺羟脯氨酸含量在3个时间点均无明显差别（P均〈0．05）。苏木精-伊红染色结果显示,N组肺组织结构正常;照射后d9,R组及R＋M组肺泡壁轻度增厚,普遍肺毛细血管扩张、充血,少量淋巴细胞、中性粒细胞浸润。小鼠肺组织透射电镜观察结果显示,照射后d30,N组及M组肺间质胶原纤维正常无增生;R组及R＋M组肺可见肺间质胶原纤维较N组及M组明显增多,但R＋M组与R组比较差别不明显。结论：6．0Cy的^60Coγ射线照射后小鼠的肺受到了损伤,但磁场没有加重这种损伤且磁疗对正常小鼠无明显肺损伤。     

川穹嗪对胸部肿瘤患者TGF-beta1水平的影响及放疗性肺损伤的预防作用

目的：探讨川穹嗪注射液对血浆TGF-beta1 水平的影响及对放射性肺损伤的预防作用。方法：随机选取120 例胸部肿瘤放疗患 者分为观察组与对照组,所有研究对象给予三维适形放射治疗,观察组在放疗期间川芎嗪注射液每日静脉滴注1 次;检测两组放 疗前后血浆TGF-beta1含量变化、放射性肺损伤及肺功能情况。结果：放疗后两组血浆TGF-beta1 均上升,观察组在放疗结束时、放疗 结束后3 月、6 月的血浆TGF-beta1 含量明显低于对照组(P<0.05) (19.12± 5.23) vs(26.69± 5.38)ng/mL、(5.62± 3.48)vs(9.64± 7.82) ng/mL、(3.28± 1.81)vs (7.98± 5.16) ng/mL;观察组放射性肺损伤发生率低于对照组(P<0.05);观察组放疗后三月肺功能指标用力肺 活量(FVC)、第1 秒用力呼气容积(FEV)、肺总量(TLC)、CO弥散量(DLCO)出现明显下降的例数显著低于对照组(P<0.05)。结论：川 芎嗪注射液可以降低放疗肺损伤患者的血浆TGF-beta1 含量,降低放射性肺炎与放射性肺纤维化的发生率,改善肺功能,无明显不 良反应、安全性好,可起到较好的预防放疗后放射性肺损伤的作用。     

Plerixafor, a CXCR4 antagonist, mitigates skin radiation-induced injury in mice

Even with modern 3D conformal treatments skin radiation injury can be an inadvertent complication associated with clinical radiotherapy particularly at tissue folds. It is also of concern in the context of a radiological terrorism incident or accident, since skin irradiation lowers the lethal dose of whole body radiation. We hypothesize that radiation-induced skin injury originates from a loss of stem and progenitor cells, accompanied by excessive ROS production and proinflammatory cytokines. Plerixafor, a CXCR-4 antagonist, is one of the most efficient bone marrow stem cell mobilizers and these studies were designed to experimentally assess the potential of Plerixafor to reduce skin radiation injury. The right hind legs of groups of C57BL/6 mice were exposed to radiation alone or in combination with Plerixafor. Plerixafor was administered intraperitoneally at a dose of 5 mg/kg given in two doses separated by two days and started either on day 0, 4, 7, 15 or 24 after irradiation. The primary end point was skin injury, which was assessed three times a week for at least 2 months using a semi-quantitative scale. Secondary end points measured at selected time points included histology (primarily H&E) and cytokine levels (TGF-β and TNF-α). The acute and late skin injury in mice receiving Plerixafor was highly dependent on the timing of administration of the drug. The maximum benefit was observed when the drug was started 1 week after radiation exposure, and earlier or later administration of the drug decreased its efficacy. Secondary damage end points (cytokine levels and histologically assessed tissue thickness) provided confirmatory observations. In an attempt to gain insight into the effect of timing of administration of the agent on the mitigation effect, the ligand to CXCR4, stromal derived factor, SDF-1, was measured as a function of time after radiation exposure. Expression of SDF-1 monitored in skin as a function of time after a 30 Gy radiation exposure suggested a strong correlation between timing of administration of Plerixafor and expression of SDF-1 in irradiated skin: optimum drug administration timing coincided with maximal SDF-1 expression in the skin of irradiated mice. This report presents the first observation that CXCR4 antagonist improves both acute and late skin response to radiation exposure. ? 2012 by Radiation Research Society.     

不同剂量x射线对大鼠精子CRISP2mRNA表达水平的影响

目的：观察不同剂量x射线对大鼠精子CRISP2mRNA表达水平的影响,探讨其在电离辐射所致大鼠精子功能改变中的作用。方法：用吸收剂量为1、2、4、和6Gy的x射线分别照射活体SD大鼠的外生殖系统1…4812、24h后,用PCR技术检测精子CRISP2基因mRNA表达水平;用光学显微镜观察精予活力。以未照射组为对照。结果：4、6GyX射线照射不同时间（1、4、8、12、24h时）后大鼠精子的CRISP2mRNA相对表达量均较对照组显著下降（P．〈0．05）,其中6Gb,照射24小时后相对表达量最低（P〈0．01）,而4Gy照射组与6Gy照射组相比较差异无统计学意义（P〉0．05）;2Gyx射线照射8h后CRISP2mRNA相对表达量下降有统计学意义（P〈0．05）;2GyX射线照射1、4h后及1GyX射线照射不同时间（1、4、8、12、24la）后大鼠精子的CRISP2mRNA相对表达量较对照组下降,但差异无统计学意义（P〉O．05）。1、2GyX射线照射不同时间（1、4、8、12、24小时）及4GyX射线照射（1、4、8h）后,精子活力与正常对照组相比无明显改变（P〉0．05）;4GyX射线照射12、24h后大鼠精子活力显著低于正常对照;6GyX射线照射不同时间（1、4、8、12、24h）后,精子活力明显低于对照组（P〈0．05）。结论：不同剂量X射线照射不同时间可导致SD大鼠精子活力下降,这可能与其下调CRISP2基因的mRNA表达水平有关。