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41.
The aim of this study was to determine whether the effect of Bax and Bcl‐2 on the apoptosis of germ cells is caused by local testicular heating (42°C, 1 hr) in boar testis. The testes of three boars were exposed to 42°C for 1 hr. Three other boars were assigned as control (no heat treatment). After 6 hr of heat treatment, all boars were castrated and the testes were harvested. Immunohistochemical results showed that a redistribution of Bax was caused by heat stress, and Bcl‐2 was expressed in the cytoplasm and nucleus. Western blot analyses and quantitative real‐time polymerase chain reaction (QRT‐PCR) showed that the protein and mRNA levels of Bax and Bcl‐2 were increased after local testicular heating. The number of TUNEL‐positive cells was increased in the seminiferous tubules compared with the control after local testicular heating. These results suggested that local testicular heating induced the apoptosis of germ cells by regulating the Bax and Bcl‐2 protein levels.  相似文献   
42.
The objective was to evaluate the toxicity effect of gossypol on ultrastructure of mouse testis and the expression of Bax mRNA and Bcl-2 mRNA of sperm cells in mice.Forty-eight male mice were randomly divided into four groups:control group,L-group(30 mg·kg~(-1)·d),M-group(60 mg·kg~(-1)·d)and H-group(120 mg·kg~(-1)·d)and were orally administrated with gossypol diluted by sodium carboxymethyl cellulose(SCC)or SCC(control group)for 20 days.On the 21st day,all the mice were killed and ultrastructure changes of testis were observed by TEM.mRNA expression of Bax and Bcl-2 in testis was measured by semiquantitative RT-PCR.The results showed that the testicular ultrastructure in three treated groups was gradually damaged,according to the dosage of gossypol and cellular structure disordered and organelle degenerated,manifesting vacuolation of mitochondria,expansion of endoplasmic reticulum.mRNA expression of Bcl-2 in testis significantly increased(p0.05)in L-group and then significantly decreased(p0.05,p0.01)in M-group and H-group compared with that in the control group;mRNA expression of Bcl-2 in M-group and H-group significantly decreased(p0.05,p0.01)than that in L-group and Bcl-2 mRNA expression in H-group showed a significant decrease(p0.05)compared with that in M-group.On the other hand,mRNA expression of Bax significant increased(p0.05,p0.01)in M-group and H-group than that in the control group.The ratio of Bcl-2/Bax significantly reduced(p0.05,p0.01)in the treated group than that in the control group and was found to be an obvious dose-dependent.It demonstrated that the gossypol could induce the changes on ultrastructure of mice testis,down-regulate mRNA expression of Bcl-2 and up-regulate mRNA expression of Bax,which indicated that sperm cells were induced apoptosis.  相似文献   
43.
试验首先对质粒pGSA1285进行改造,将pFGC5941质粒的查尔酮合酶的Intron片段取代pGSA1285的GUS片段,构建含有内含子并具有卡那抗性的pGSA2285植物沉默表达载体。同时设计引物、PCR扩增、在BI-1基因两端各加上两个酶切位点,将BI-1基因分别反向、正向插入改造后的质粒pGSA2285Intron片段两端的多克隆位点中,构建得到烟草BI-1基因沉默载体pGSA4285。此沉默质粒经PCR鉴定、限制性酶切分析以及回复动员试验证明已正确构建并成功转入农杆菌,为获得含有BI-1基因沉默烟草植株及其在植物程序性死亡中调控作用的研究奠定试验基础。  相似文献   
44.
为了探讨脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)对体外培养仓鼠肾细胞(BHK-21)的线粒体膜电位及Bax和Bcl-2蛋白表达的影响,采用细胞培养、流式细胞术、免疫细胞化学染色等方法,研究DON对细胞早期凋亡率、线粒体膜电位及Bax和Bcl-2蛋白表达的变化.结果显示:不同浓度的DON均可诱导BHK-21细胞凋亡,各浓度组的凋亡率都显著高于对照组(P<0.05);DON可使BHK-21细胞线粒体膜电位下降,且表现出剂量和时间效应关系.免疫组织化学染色显示,DON处理细胞24 h,Bax蛋白表达显著高于对照组,而Bcl-2蛋白表达均低于对照组.上述结果表明:DON诱导了BHK-21细胞凋亡和线粒体膜电位下降,Bax表达增强而Bcl-2表达下降是DON诱导BHK-21细胞凋亡的分子机制之一.  相似文献   
45.
目的 通过观察马归液对腺性膀胱炎大鼠模型膀胱组织的影响,为运用马归液治疗腺性膀胱炎提供实验基础和理论依据。方法 首先通过对大鼠膀胱灌注大肠埃希菌成功建立腺性膀胱炎大鼠模型,然后对造模成功的大鼠分别灌注马归液第1组为1次/周;马归液第2组为2次/周、吡柔比星、生理盐水8周,再对各组大鼠膀胱组织进行病理学检查、透射电镜检测和Bcl-2、Bax基因表达检测,以观察各组大鼠膀胱黏膜组织结构的变化。结果 经马归液灌注,马归液1组、马归液2组病理学检查显示膀胱组织正常无炎性病变;Bax、Bcl-2灰度均值比较,马归液2组、马归液1组的灰度均值与生理盐水组比较,均有统计学意义(P<0.05),马归液2组与马归液1组比较,无统计学意义(P>0.05);Bcl-2/Bax中,马归液1组、马归液2组分别与吡柔比星组、生理盐水组组间比较中均有统计学意义(P<0.05),马归液2组与马归液1组比较无统计学意义(P>0.05)。结论 马归液对大鼠腺性膀胱炎膀胱黏膜有明显治疗效果,具有修复作用,且一周灌注两次疗效最佳。  相似文献   
46.
【目的】研究褪黑激素对内蒙古绒山羊皮肤Bcl-2和Bax基因表达的影响,探讨Bcl-2和Bax基因以及褪黑激素与绒山羊绒毛生长和凋亡的关系。【方法】选用8只性别、体重、年龄一致的内蒙古绒山羊母羊,随机分为埋植组和对照组,提取皮肤总RNA,对Bcl-2和Bax基因mRNA表达进行相对定量分析。【结果】①Bcl-2和Bax基因在内蒙古绒山羊皮肤细胞中相对表达量比值(Bcl-2/Bax)的增减与绒山羊一年中绒毛生长、退行以及休止时间特点基本吻合;②褪黑激素对Bcl-2基因在内蒙古绒山羊皮肤中的表达无显著影响(P>0.05),但显著上调了Bax基因在各月份的表达(P<0.01)。【结论】褪黑激素显著下调了Bcl-2和Bax基因在内蒙古绒山羊皮肤细胞中相对表达量的比值(Bcl-2/Bax),可促进细胞凋亡,加快机体新陈代谢。  相似文献   
47.
利用农杆菌侵染获得转番茄Bax inhibitor-1(LeBI-1)基因的抗性烟草植株,进行了PCR鉴定和共聚焦扫描显微镜检测;同时以MS为基本培养基研究植物生长调节剂的最佳配比和浓度对建立野生型和转基因烟草悬浮细胞素的影响。结果表明:PCR鉴定为阳性,并检测到绿色荧光蛋白,而且6-BA浓度在0.2 mg/L、NAA浓度为2.0 mg/L条件下,可建立野生型和转基因烟草稳定的悬浮细胞系。  相似文献   
48.
The plasmid pGSA1285 was first modified by substituting its GUS sequence with the Chalcone synthase intron fragment from vector pFGC5941 to get the plant silencing expression vector that contained Kanamycin resistance site and was named as pGSA2285. Using PCR-based amplification, two different restriction sites at both ends of tobacco Bax inhibitor-1 (NtBI-1) gene were created, respectively, which made the construction of ihpRNA gene silencing vector more efficiently. Then, NtBI-1 genes were inserted into M...  相似文献   
49.
3-甲基-4-硝基酚对大鼠睾丸组织的损伤作用   总被引:1,自引:0,他引:1  
为从病理学角度探讨3-甲基-4-硝基酚(PNMC)的生殖毒性,采用24只SPF雄性SD大鼠随机分为4组,染毒组分为100 mg/kg体重、10 mg/kg体重和1 mg/kg体重三组,连续5 d皮下注射,对照组皮下注射等量的溶剂(PBS+0.05%tween80)。最后一次染毒后24 h,无痛处死大鼠,称取睾丸湿重并计算其指数。将已固定的睾丸组织进行石蜡切片,采用H.E和免疫组化染色的方法观察PNMC对大鼠睾丸的病理损伤及其对凋亡相关蛋白Bcl-2和Bax表达的影响。结果显示各个染毒组与对照组相比较,睾丸大体湿重和睾丸指数明显下降(P0.05或P0.01);H.E染色结果显示各试验组睾丸曲细精管生精细胞均有不同程度的空泡变性兼或坏死;免疫组织化学染色观察发现:各实验组睾丸中Bax蛋白表达量显著高于对照组(P0.01),而Bc1-2蛋白表达量却明显低于对照组(P0.01),Bc1-2/Bax也显著低于对照组(P0.01)。研究结果表明,PNMC不仅可引起雄性大鼠睾丸曲细精管生精细胞变性、坏死,还可促进生殖细胞的大量凋亡。  相似文献   
50.
AIM: To investigate matrine-induced apoptosis of human medulloblastoma D341 cells and the expression of Bax, Bcl-2, serine/threonine kinase Akt and phosphorylated Akt (p-Akt) in vitro. METHODS: D341 cells were divided into experimental groups (added with matrine at different concentrations) and control group (under the same conditions without matrine). The proliferation of D341 cells was analyzed by CCK-8 assay. Apoptosis was detected by Annexin V-FITC/PI double staining and the expression of Bax, Bcl-2, Akt and p-Akt was detected by Western blotting. RESULTS: Matrine significantly inhibited the proliferation of D341 cells and increased the apoptosis in a dose- and time-dependent manner. The cell apoptosis was characterized by chromatin condensation with margination of chromatin to the nuclear membrane, increased when and larger cytoplasmic vacuoles, and formation of apoptotic body after treatment with matrine. The expression of Bax increased, while the expression of Bcl-2 and p-Akt decreased when the drug concentration gradually increased. CONCLUSION: Matrine induces the apoptosis of human medulloblastoma D341 cells in vitro by activation of Bax, down-regulation of Bcl-2 and reduction of p-Akt expression level in the PI3K/Akt signaling pathway.  相似文献   
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