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1.
摘要 目的:探讨苍耳子对慢性鼻-鼻窦炎大鼠炎症反应、NLRP3炎症小体及JAK2STAT3信号通路的影响。方法:选择清洁级SD大鼠40只作为研究对象。将40只大鼠随机分为5组。采用鼻腔内注射金黄色葡萄球菌悬浊液的方法构建慢性鼻-鼻窦炎大鼠模型。空白对照组(8只)、模型组(8只)、低剂量组(7.5 mg/kg,8只)、中剂量组(15 mg/kg,8只)和高剂量组(30 mg/kg,8只)。采用埋藏食物小球实验进行嗅觉功能检查,采用qRC-PCR检测JAK2/STAT3信号通路和NLRP3、ACS、caspase-1的mRNA表达水平并采用ELISA法检查大鼠血液样本中肿瘤坏死因子-α(TNF-α)和IL-1β、IL-18的表达水平。结果:建模前,各组大鼠找到食物小球的时间比较(P>0.05);治疗后7 d和治疗完成时,与对照组相比,模型组、低剂量组、中剂量组和高剂量组找到食物小球的时间明显更长(P<0.05),高剂量组找到食物小球的时间明显短于模型组、低剂量组、中剂量组(P<0.05)。与对照组相比,模型组、低剂量组、中剂量组和高剂量组JAK2 mRNA、STAT3 mRNA相对表达水平明显更高(P<0.05),高剂量组JAK2 mRNA、STAT3 mRNA相对表达水平明显低于模型组、低剂量组、中剂量组(P<0.05)。与对照组相比,模型组、低剂量组、中剂量组和高剂量组TNF-α、IL-1β、IL-18表达水平明显更高(P<0.05),高剂量组TNF-α、IL-1β、IL-18表达水平明显低于模型组、低剂量组、中剂量组(P<0.05)。与对照组相比,模型组、低剂量组、中剂量组和高剂量组NLRP3 mRNA、ACS mRNA、caspase-1 mRNA相对表达水平明显更高(P<0.05),高剂量组NLRP3 mRNA、ACS mRNA、caspase-1 mRNA相对表达水平明显低于模型组、低剂量组、中剂量组(P<0.05)。结论:CRS大鼠采用苍耳子挥发油进行治疗可通过调控JAK2/STAT3信号通路的表达和NLRP3炎症小体的表达,从而抑制下游炎症因子的过度分泌,最终为缓解CRS病情和改善嗅觉功能做出贡献。  相似文献   

2.
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。  相似文献   

3.
摘要 目的:研究川陈皮素对脑梗死缺血再灌注大鼠的保护作用及其机制。方法:将90只雄性Wistar大鼠随机分为空白对照组、假手术组、模型组及低剂量组、中剂量组及高剂量组,每组15只。空白对照组不予以任何处理,模型组、低剂量组、中剂量组及高剂量组其余各组大鼠均采用Long线栓法构建脑梗死缺血再灌注模型,假手术组除了不插入拴线,其他操作和模型组相同。造模后,空白对照组、假手术组及模型组分别予以10 mL/(kg?d)的生理盐水灌胃,低剂量组、中剂量组、高剂量组分别予以10 mL/(kg?d)、15 mL/(kg?d)、20 mL/(kg?d)川陈皮素灌胃。检测各组大鼠梗死面积以及神经细胞凋亡率,缺氧诱导因子-1α(HIF-1α)、血管内皮生长因子(VEGF)水平,炎症细胞因子水平,B淋巴细胞瘤-2(Bcl-2),Bcl-2相关X蛋白(Bax),半胱氨酸天冬氨酸蛋白酶-3(caspase-3)表达情况。结果:模型组、低剂量组、中剂量组、高剂量组梗死面积、神经细胞凋亡率以及HIF-1α、肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-β)、Bax mRNA、caspase-3 mRNA水平均高于空白对照组及假手术组;且低剂量组、中剂量组、高剂量组较模型组低;降低呈剂量依赖性(均P<0.05)。模型组、低剂量组、中剂量组、高剂量组VEGF、Bcl-2 mRNA水平均低于空白对照组及假手术组;且低剂量组、中剂量组、高剂量组较模型组高;降低呈剂量依赖性(均P<0.05)。假手术组梗死面积以及神经细胞凋亡率均高于空白对照组(均P<0.05)。结论:川陈皮素对脑梗死缺血再灌注大鼠的保护作用明显,其主要机制可能与调控HIF-1α、VEGF、炎症细胞因子以及凋亡相关基因表达有关。  相似文献   

4.
摘要 目的:探讨小檗碱对缺血性脑梗死大鼠氧化应激/炎症反应、血管生成的作用。方法:选取60只SPF级SD大鼠,随机分为对照组、模型组和小檗碱组各20只。建立大鼠脑缺血再灌注损伤模型。术后及给药后7d采用Longa标准评分评估大鼠神经功能。检测各组大鼠脑组织的抗氧化活性和炎症因子水平。采用免疫组化检测脑缺血再灌注皮质微血管密度(MVD)。采用实时定量聚合酶链反应(qRT-PCR)检测低氧诱导生长因子- 1 (HIF-1 )和血管内皮生长因子(VEGF) mRNA表达水平。采用蛋白免疫印迹试验检测VEGF和HIF-1 蛋白表达水平。结果:模型组和小檗碱组大鼠术后具有神经功能缺损症状表现,Longa评分均高于对照组。给药7 d后,模型组和小檗碱组大鼠Longa评分均高于对照组(P<0.05),且小檗碱组大鼠Longa评分低于模型组(P<0.05)。与对照组比较,模型组丙二醛(MDA)水平显著升高,而谷胱甘肽过氧化物酶(GSH-Px)和超氧化物岐化酶(SOD)活性显著降低(P<0.05)。与模型组比较,小檗碱组MDA水平显著降低,而GSH-Px和SOD活性显著升高(P<0.05)。与对照组比较,模型组白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)水平显著升高(P<0.05)。与模型组比较,小檗碱组IL-1β、TNF-α水平显著降低,差异有统计学意义(P<0.05)。给药7 d后,模型组和小檗碱组MVD、VEGF mRNA和HIF-1 mRNA表达水平均高于对照组(P<0.05),而小檗碱组MVD、VEGF mRNA和HIF-1 mRNA表达水平高于模型组(P<0.05)。给药7 d后,小檗碱组和模型组VEGF和HIF-1 蛋白表达水平均高于对照组(P<0.05),而小檗碱组VEGF和HIF-1 蛋白表达水平高于模型组(P<0.05)。结论:小檗碱通过抑制氧化应激/炎症反应、促进血管生成从而达到脑保护作用,其机制可能与激活HIF-1 /VEGF信号通路有关。  相似文献   

5.
摘要 目的:探讨芪参地黄颗粒对实验性自身免疫性重症肌无力(EAMG)大鼠B细胞介导的免疫机制。方法:通过Rα97-116肽段和完全弗氏佐剂免疫,成功将30只Lewis大鼠构建EAMG模型,将EAMG大鼠随机分为模型组、芪参地黄颗粒低、中、高剂量组和阳性药组,每组6只。进一步观察大鼠体重及临床症状,检测血清中乙酰胆碱受体抗体(AChR-Ab)含量、脾脏组织CD19和CD27的蛋白表达、B淋巴细胞刺激因子(BAFF)、B细胞趋化因子CXC配体13(CXCL13)、C-X-C趋化因子受体5型(CXCR5) mRNA表达。结果:经给药治疗后芪参地黄颗粒低、中、高剂量组和阳性药组与模型组相比体重增加(P<0.05),临床症状评分均下降(P<0.05)。经给药治疗后,与模型组相比,芪参地黄颗粒低、中、高剂量组血清中AChR-Ab含量均降低(P<0.05),芪参地黄颗粒中、高剂量组脾脏组织CD27蛋白表达、CD19蛋白表达和BAFF mRNA表达降低(P<0.05),芪参地黄颗粒高剂量组脾脏组织CXCL13和CXCR5 mRNA表达降低(P<0.05),且芪参地黄颗粒中、高剂量组脾脏组织CD19蛋白表达较阳性药组下降(P<0.05)。结论:芪参地黄颗粒通过降低EAMG大鼠CD19和CD27蛋白、BAFF、CXCL13和CXCR5 mRNA的表达,减少B细胞的分化增殖,抑制B细胞产生AChR-Ab,减少对乙酰胆碱受体的破坏,使EAMG大鼠体重增加,临床症状得到改善。  相似文献   

6.
摘要 目的:探讨补肝健腰方对大鼠腰椎间盘退变模型中碱性成纤维细胞生长因子(bFGF)、转化生长因子-β1(TGF-β1)、骨形态发生蛋白-3(BMP-3)表达的影响。方法:取SD大鼠90只,随机分为正常对照组、假手术组、模型组、低、中、高剂量补肝健腰方组,每组各15只,正常对照组不予处理,假手术组仅暴露椎间盘而不做椎间盘穿刺,余四组制备大鼠腰椎间盘退变模型,造模成功后,分别给予低、中、高剂量补肝健腰方组低、中、高剂量补肝健腰方药液灌胃;正常对照组、假手术组、模型组给予等量生理盐水灌胃,检测各组干预前、20 d后、40 d后椎间盘TGF-β1、bFGF mRNA及BMP-3含量。结果:与正常对照组及假手术组相比,模型组及补肝健腰方各剂量组干预前TGF-β1、bFGF mRNA及BMP-3的表达均上升(P<0.05) , 干预20 d、40 d后补肝健腰方各剂量组TGF-β1、bFGF mRNA及BMP-3的表达上升(P<0.05)。与模型组相比,补肝健腰方各剂量组干预前TGF-β1、bFGF mRNA及BMP-3的含量未见明显变化(P>0.05),干预20 d后补肝健腰方各剂量TGF-β1、bFGF mRNA及BMP-3的表达均下降(P<0.05),干预40 d后补肝健腰方高剂量组与中剂量组TGF-β1、bFGF mRNA及BMP-3的表达下降更为明显(P<0.05),低剂量组中TGF-β1、bFGF mRNA及BMP-3的表达也下降(P<0.05)。干预40 d后补肝健腰方高剂量组、中剂量组较低剂量组TGF-β1、bFGF mRNA及BMP-3的表达下降更为明显(P<0.05)。结论:补肝健腰方能降低大鼠腰椎间盘退变模型中bFGF、TGF-β1、BMP-3的表达,促使退变的椎间盘修复,且呈剂量依赖性。  相似文献   

7.
目的:应用Cat Sper1单克隆抗体抑制Cat Sper1的功能,检测精子线粒体呼吸功能及能量合成能力,观察Cat Sper1对精子线粒体呼吸与能量代谢的影响。方法:健康志愿者20例,检测精液均符合WHO健康标准。手淫法获取精液,经过上游法处理后每份精液分为A、B两组,分别与Earles液以及50μg/m L抗Cat Sper1多克隆抗体共孵育。在1 h,2 h,4 h后分别检测两组精子精液参数、细胞线粒体呼吸控制率RCR及精子细胞ATP含量。结果:与A组比较,B组精子各时间点a+b(%)尤其是a(%)均明显下降,差异具有统计学意义(P0.01);1 h后B组精子a(%)即明显下降,2 h,4 h后精子下降缓慢,与1 h相比无明显差异,无统计学意义(P0.05)。与A组比较,B组精子各时间点态3值、呼吸控制率RCR以及精子细胞ATP含量均明显下降,差异具有统计学意义(P0.01);B组精子中,2 h、4 h节点精子态3值、呼吸控制率RCR以及精子细胞ATP含量与1 h无明显差异,无统计学意义(P0.05)。结论:阻断精子特异性钙通道Cat Sper1,可降低精子细胞线粒体呼吸功能,减少精子生成ATP的能力,从而使精子活力降低。为精索静脉曲张引起精子Cat Sper1表达下降,从而导致不育的机制寻找可能的理论依据。  相似文献   

8.
摘要 目的:探讨骨髓间充质干细胞(BMSCs)移植对急性肝功能衰竭(ALF)大鼠肝再生、炎症反应及转换生长因子-β受体(TGF-βR)的影响。方法:将90只SD级大鼠以随机数表法分成模型组(n=30)、健康组(n=30)及治疗组(n=30)。健康组不予以任何处理,模型组和治疗组大鼠则通过四氯化碳蓖麻油溶液腹腔注射制作ALF大鼠模型,治疗组大鼠取BMSCs通过门静脉注射治疗,模型组则予以等量生理盐水干预。造模后第7 d,比较三组大鼠的肝功能指标水平,炎症反应以及TGF-βR相关指标表达情况,并进行相关性分析。结果:模型组与治疗组大鼠血清谷丙转氨酶(ALT)、谷草转氨酶(AST)以及总胆红素(TBIL)水平均高于健康组,但治疗组大鼠上述肝功能指标水平低于模型组(均P<0.05)。模型组与治疗组大鼠血清肿瘤坏死因子-α(TNF-α)水平以及肝组织TNF-α mRNA表达均高于健康组,但治疗组大鼠血清TNF-α水平以及肝组织TNF-α mRNA表达低于模型组(均P<0.05)。模型组与治疗组大鼠TGF-βR1和TGF-βR2蛋白表达均高于健康组,但治疗组大鼠上述蛋白表达低于模型组(均P<0.05)。经Spearman相关性分析发现:ALT、AST及TBIL水平与血清TNF-α、TNF-α mRNA及TGF-βR1、TGF-βR2蛋白表达水平均呈正相关关系(均P<0.05)。结论:BMSCs移植在促进ALF大鼠肝再生方面效果显著,且有效减轻炎症反应、下调TGF-βR1和TGF-βR2表达水平。  相似文献   

9.
摘要 目的:探讨姜黄素衍生物减缓大鼠糖尿病周围神经病变(DPN)进展的作用及其机制。方法:30只健康成年雄性SD大鼠随机分为3组,每组10只;构建链脲佐菌素(STZ)诱导的DPN大鼠模型;研究组1按10 mg/kg体重喂养10 μM的姜黄素衍生物;研究组2按10 mg/kg体重喂养100 μM的姜黄素衍生物;对照组喂养同等量的生理盐水。利用Von Frey电子测痛仪检测各组大鼠痛觉机械戒断阈值(MWT)。采用实时定量聚合酶链反应(qRT-PCR)和蛋白免疫印迹试验检测AMPK、mTOR mRNA和蛋白表达水平。最后测定活化剂AICAR处理的RSC96细胞中mTOR的表达水平。结果:喂养姜黄素衍生物大鼠的痛觉机械戒断阈值(MWT)随时间推移逐渐降低,与对照组相比,研究组1大鼠的MWT显著降低,而研究组2大鼠的MWT也显著低于研究组1,差异均有统计学意义(P<0.05)。与对照组相比,研究组1的AMPK mRNA和蛋白表达水平显著升高,mTOR mRNA和蛋白表达水平表达显著降低(P<0.05);而研究组2的AMPK mRNA和蛋白表达水平显著高于研究组1,mTOR mRNA和蛋白表达水平显著低于研究组1,差异均有统计学意义(P<0.05)。使用活化剂AICAR处理RSC96细胞后,活化剂AICAR组的mTOR mRNA和mTOR蛋白表达水平明显低于非活化剂组,差异有统计学意义(P<0.05)。结论:姜黄素衍生物可能通过AMPK调节mTOR信号通路改善DPN,其可能具有潜在的治疗DPN的能力。  相似文献   

10.
目的:分析右归丸对膝骨性关节炎(KOA)大鼠Wnt信号通路相关因子表达的影响,探讨右归丸对KOA大鼠的保护机制。方法:SPF级SD大鼠60只,按照体重法随机分为假手术组、模型组、硫酸氨基葡萄糖组、右归丸高、中、低剂量组(n=10)。采用改良Hulth法复制膝骨关节炎大鼠模型。右归丸高中低剂量组分别按20、10、5 g/kg灌服相应的药物,硫酸氨基葡萄糖组按0.17 g/kg灌服硫酸氨基葡萄糖,假手术组和模型组灌服等体积的生理盐水,干预8周。末次给药后摘取膝关节,通过膝关节病理切片观察各组大鼠软骨组织病理改变;采用RT-PCR法对各组大鼠软骨组织DKK1、WISP1、Wnt1、β-catenin和LRP5 mRNA的表达水平进行对比分析;通过Western blot法检测各组大鼠软骨组织DKK1、WISP1、Wnt1、LRP5和β-catenin的蛋白质含量的变化。结果:与假手术组比较,模型组大鼠关节软骨受损严重,Mankin评分明显升高(P<0.05);DKK1 mRNA表达水平和蛋白质表达水平明显降低(P<0.05);WISP1、Wnt1、β-catenin、LRP5 mRNA表达水平及蛋白质表达水平明显升高(P<0.05)。与模型组比较,右归丸高剂量组和硫酸氨基葡萄糖组关节软骨病变明显减轻;Mankin评分明显减轻(P<0.05);大鼠软骨组织中DKK1 mRNA表达水平和蛋白表达水平明显升高,WISP1、Wnt1、β-catenin、LRP5 mRNA及蛋白表达水平显著降低(P<0.05)。结论:右归丸通过抑制Wnt信号通路中WISP1、Wnt1、β-catenin、LRP5的表达,促进DKK1细胞因子的表达,发挥对KOA的保护作用。  相似文献   

11.
12.
In order to fertilize, mammalian sperm must hyperactivate. Hyperactivation is triggered by increased flagellar Ca(2+), which switches flagellar beating from a symmetrical to an asymmetrical pattern by increasing bending to one side. Thimerosal, which releases Ca(2+) from internal stores, induced hyperactivation in mouse sperm within seconds, even when extracellular Ca(2+) was buffered with BAPTA to approximately 30 nM. In sperm from CatSper1 or CatSper2 null mice, which lack functional flagellar alkaline-activated calcium currents, 50 microM thimerosal raised the flagellar bend amplitudes from abnormally low levels to normal pre-hyperactivated levels and, in 20-40% of sperm, induced hyperactivation. Addition of 1 mM Ni(2+) diminished the response. This suggests that intracellular Ca(2+) is abnormally low in the null sperm flagella. When intracellular Ca(2+) was reduced by BAPTA-AM in wild-type sperm, they exhibited flagellar beat patterns more closely resembling those of null sperm. Altogether, these results indicate that extracellular Ca(2+) is required to supplement store-released Ca(2+) to produce maximal and sustained hyperactivation and that CatSper1 and CatSper2 are key elements of the major Ca(2+) entry pathways that support not only hyperactivated motility but possibly also normal pre-hyperactivated motility.  相似文献   

13.
The purpose of this study was to investigate the effect of clomiphene citrate and human chorionic gonadotropin (HCG) on the structural changes, as well as the evaluation of the expression of cation channel sperm‐associated protein 1 (CatSper1), cation channel sperm‐associated protein 2 (CatSper2), luteinizing hormone/choriogonadotropin receptor (LHCGR), and steroidogenic factor 1 (SF1) genes in testicular tissue of rats. All rats divided into five groups as follows; G1 as the control group that received normal saline, G2 received olive oil, G3 received 100 IU/kg HCG, G4 received 5 mg/kg clomiphene citrate, and G5 received 5 mg/kg clomiphene citrate and 100 IU/kg HCG. At the end of the experiment period, Day 56, blood samples were taken and the serum was isolated. Then, histomorphometric analysis, hormonal assess, and real‐time polymerase chain reaction to measure the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were performed. The results showed that the concentrations of testosterone, follicle‐stimulating hormone, and luteinizing hormone were decreased in the G4 group, whereas these parameters were increased in the G3 group. A comparison of the sperm quality indicated a significant reduction in the quality of sperm cells in the G4 group compared with other groups. The quality of sperm was significantly enhanced in the G3 and G5 groups in comparison with the G1 group. Also, our findings demonstrated that the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were significantly elevated in the G3 group when compared with other experimental groups. According to the obtained results, it seems that clomiphene citrate reduces the process of spermatogenesis and the detrimental impacts of this compound would be neutralized by the administration of HCG.  相似文献   

14.
Sperm guidance is controlled by chemical and physical cues. In many species, Ca2+ bursts in the flagellum govern navigation to the egg. In Arbacia punctulata, a model system of sperm chemotaxis, a cGMP signaling pathway controls these Ca2+ bursts. The underlying Ca2+ channel and its mechanisms of activation are unknown. Here, we identify CatSper Ca2+ channels in the flagellum of A. punctulata sperm. We show that CatSper mediates the chemoattractant-evoked Ca2+ influx and controls chemotactic steering; a concomitant alkalization serves as a highly cooperative mechanism that enables CatSper to transduce periodic voltage changes into Ca2+ bursts. Our results reveal intriguing phylogenetic commonalities but also variations between marine invertebrates and mammals regarding the function and control of CatSper. The variations probably reflect functional and mechanistic adaptations that evolved during the transition from external to internal fertilization.  相似文献   

15.

Background  

CatSper1 and CatSper2 are two recently identified channel-like proteins, which show sperm specific expression patterns. Through targeted mutagenesis in the mouse, CatSper1 has been shown to be required for fertility, sperm motility and for cAMP induced Ca2+ current in sperm. Both channels resemble a single pore forming repeat from a four repeat voltage dependent Ca2+ /Na+ channel. However, neither CatSper1 or CatSper2 have been shown to function as cation channels when transfected into cells, singly or in conjunction. As the pore forming units of voltage gated cation channels form a tetramer it has been suggested that the known CatSper proteins require additional subunits and/or interaction partners to function.  相似文献   

16.
122 randomly selected Vrindavani cattle were studied to detect polymorphism in four fragments of the CatSper2 gene that were comprised of exon 2, 4, 5, and 6 with flanking regions. Using PCR-SSCP and sequencing analysis, three SNPs (T157C, C273A, and A274C) in the first fragment, one SNP (C30G) in the second fragment, and two SNPs (T86G and T292C) in the fourth fragment were identified. The third fragment did not reveal any polymorphism. The SNPs were used for construction of haplotypes and three haplotypes were found. The least square analysis of variance revealed a significant (P?G or C>T SNPs may not play a role in sperm motility. However, when the comparison was made between haplotype I and II, it can be inferred that C>T SNP may have a role in sperm motility, as haplotype II has better motility parameters. Expression profiling of Catper2 gene revealed nonsignificant down regulation of CatSper2 gene in poor motility sperm compared to good motility sperm.  相似文献   

17.

Background  

CatSper1-4 are a unique family of sperm cation channels, which are exclusively expressed in the testis and play an important role in sperm motility and male fertility. Despite their vital role in male fertility, almost nothing is known about the factors regulating their expression. Here, we investigated the effects of selenium (Se) on the expression of CatSper genes and sperm parameters in aging versus young male mice.  相似文献   

18.
CatSperbeta, a novel transmembrane protein in the CatSper channel complex   总被引:2,自引:0,他引:2  
Four CatSper ion channel subunit genes (CatSpers 1-4) are required for sperm cell hyperactivation and male fertility. The four proteins assemble (presumably as a tetramer) to form a sperm-specific, alkalinization-activated Ca(2+)-selective channel. We set out to identify proteins associating with CatSper that might help explain its unique role in spermatozoa. Using a transgenic approach, a CatSper1 complex was purified from mouse testis that contained heat shock protein 70-2, a testis-specific chaperone, and CatSperbeta, a novel protein with two putative transmembrane-spanning domains. Like the CatSper ion channel subunits, CatSperbeta was restricted to testis and localized to the principal piece of the sperm tail. CatSperbeta protein is absent in CatSper1(-/-) sperm, suggesting that it is required for trafficking or formation of a stable channel complex. CatSperbeta is the first identified auxiliary protein to the CatSper channel.  相似文献   

19.
The CatSper channel: a polymodal chemosensor in human sperm   总被引:1,自引:0,他引:1  
The sperm-specific CatSper channel controls the intracellular Ca(2+) concentration ([Ca(2+)](i)) and, thereby, the swimming behaviour of sperm. In humans, CatSper is directly activated by progesterone and prostaglandins-female factors that stimulate Ca(2+) influx. Other factors including neurotransmitters, chemokines, and odorants also affect sperm function by changing [Ca(2+)](i). Several ligands, notably odorants, have been proposed to control Ca(2+) entry and motility via G protein-coupled receptors (GPCRs) and cAMP-signalling pathways. Here, we show that odorants directly activate CatSper without involving GPCRs and cAMP. Moreover, membrane-permeable analogues of cyclic nucleotides that have been frequently used to study cAMP-mediated Ca(2+) signalling also activate CatSper directly via an extracellular site. Thus, CatSper or associated protein(s) harbour promiscuous binding sites that can host various ligands. These results contest current concepts of Ca(2+) signalling by GPCR and cAMP in mammalian sperm: ligands thought to activate metabotropic pathways, in fact, act via a common ionotropic mechanism. We propose that the CatSper channel complex serves as a polymodal sensor for multiple chemical cues that assist sperm during their voyage across the female genital tract.  相似文献   

20.
[Ca2+]i signaling regulates sperm motility, enabling switching between functionally different behaviors that the sperm must employ as it ascends the female tract and fertilizes the oocyte. We report that different behaviors in human sperm are recruited according to the Ca2+ signaling pathway used. Activation of CatSper (by raising pHi or stimulating with progesterone) caused sustained [Ca2+]i elevation but did not induce hyperactivation, the whiplash-like behavior required for progression along the oviduct and penetration of the zona pellucida. In contrast, penetration into methylcellulose (mimicking penetration into cervical mucus or cumulus matrix) was enhanced by activation of CatSper. NNC55-0396, which abolishes CatSper currents in human sperm, inhibited this effect. Treatment with 5 μm thimerosal to mobilize stored Ca2+ caused sustained [Ca2+]i elevation and induced strong, sustained hyperactivation that was completely insensitive to NNC55-0396. Thimerosal had no effect on penetration into methylcellulose. 4-Aminopyridine, a powerful modulator of sperm motility, both raised pHi and mobilized Ca2+ stored in sperm (and from microsomal membrane preparations). 4-Aminopyridine-induced hyperactivation even in cells suspended in Ca2+-depleted medium and also potentiated penetration into methylcellulose. The latter effect was sensitive to NNC55-039, but induction of hyperactivation was not. We conclude that these two components of the [Ca2+]i signaling apparatus have strikingly different effects on sperm motility. Furthermore, since stored Ca2+ at the sperm neck can be mobilized by Ca2+-induced Ca2+ release, we propose that CatSper activation can elicit functionally different behaviors according to the sensitivity of the Ca2+ store, which may be regulated by capacitation and NO from the cumulus.  相似文献   

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