基因对雄性生殖细胞凋亡调控的研究进展

生殖细胞凋亡是维持精子正常发生及导致少精或无精的重要因素,生精异常是诱发男性不育、生殖系统肿瘤等生殖系统疾病的原因之一.生殖细胞凋亡受多种因素控制,从基因水平研究雄性生殖细胞凋亡的过程将有助于揭示各种因素相互间作用的关系.作者就近些年对一些基因如Bc1-2基因家族、p53抑癌基因、Fas/FasL系统等在雄性生殖细胞凋亡调控中作用的研究进行了综述.目的是从分子水平上阐明生殖细胞凋亡的机理,为相关生殖系统疾病的治疗提供理论基础.     

生殖激素与哺乳动物卵泡细胞凋亡

生殖激素能够精确地调节生殖系统的发育活动,通过下丘脑-垂体-性腺轴发挥其微妙的生殖调节作用,促进卵泡的发育.调节凋亡的因素很多,激素在其中起着重要的作用.本文主要介绍不同生殖激素在卵泡发育中对卵泡发育和凋亡的影响.     

浅谈生殖激素在奶牛繁殖中的应用

浅谈生殖激素在奶牛繁殖中的应用○黑龙江省牡丹江市畜牧局（１５７００９）刘文国生殖激素可直接调节母畜的发情、排卵、生殖细胞在生殖道内的运行、胚胎附植、怀孕、分娩、泌乳，以及公畜精子的生成、副性腺分泌等功能。１生殖激素的分类及其作用１．１释放激素１．促性...     

细胞凋亡与生殖

通过改变基因的表达或激素水平 ,可人为地调节生殖细胞的凋亡 ,对于了解生殖系统疾病及其本质和防治方法具有非常重要的意义。本文就生殖细胞凋亡的现象、生殖细胞凋亡的调节及其基因调控等诸多方面作一综述     

生殖激素在绒山羊繁殖方面的应用

绒山羊生殖活动是一个极为复杂的过程，如母羊卵子的发生、排出，发情的周期变化；公羊精子的发生及交配活动；生殖细胞在生殖道内的运行；胚胎的附植及其在子宫内的发育；母羊的妊娠、分娩及泌乳活动等。这些生理活动都与生殖激素的作用有着密切的关系。体内的许多激素都直接或间接、或多或少地参与生殖活动调节。一旦分泌生殖激素的组织和器官活动失去平衡，就会导致生殖机能紊乱，造成繁殖力下降，甚至不育。     

坏死性凋亡对卵巢生殖细胞影响的研究进展

坏死性凋亡作为一种程序性死亡方式,参与卵泡发育、黄体分解等生殖过程,但其在哺乳动物卵巢生殖细胞上的具体机制尚未阐明。本文综述了坏死性凋亡具体分子机制、鉴定手段及其对哺乳动物卵巢生殖细胞发育影响的研究进展,以期为坏死性凋亡在哺乳动物卵巢生殖细胞上的深入研究提供理论参考。     

生殖激素在奶牛繁殖中的应用

生殖激素在奶牛繁殖中的应用刘文国（黑龙江牡丹江市畜牧局１５７００９）直接作用于生殖活动，并以调节生殖过程为主要生理功能的激素称为生殖激素。它可直接调节母畜的发情、排卵、生殖细胞在生殖道内的运行、胚胎附植、怀孕、分娩、泌乳，以及公畜精子的生成、副性腺分...     

生殖激素控制卵泡细胞凋亡的研究进展

研究表明颗粒细胞凋亡是导致卵泡闭锁的重要原因，而颗粒细胞凋亡涉及许多因素，其中生殖激素，如GnRH、FSH、LH、P4、E、A、GH、Mel、inhibin、activin、follistatin等间接地和直接地对卵巢卵泡细胞凋亡发挥重要的综合控制作用，因此正确理解激素对体内、外卵泡及颗粒细胞发育和衰亡的调节网络具有很重要的理论和实践意义。     

浅谈生殖激素在奶牛繁殖中的应用

生殖激素是直接作用于生殖活动,并以调节生殖过程为主要生理功能的激素。在生殖过程中具有直接调节母畜的发情、排卵、生殖细胞在生殖道内的运行、胚胎附植、怀孕、分娩、泌乳、以及公畜精子的生产、副性腺分泌等功能。在奶牛繁殖中的运用更是广泛,笔者在临床解决奶牛繁殖障碍病的治疗     

牛卵子发生过程中卵母细胞凋亡的调控机理

细胞凋亡是发育过程中的基本生命现象,除各种体细胞凋亡外,生殖细胞的发生过程中也发生细胞凋亡。就雌性生殖系而言,细胞凋亡是其发育过程中的一个重要组成部分。在母牛中,超过99.9%的雌性生殖细胞都会在卵子发生的不同阶段发生凋亡。本文主要综述了牛卵子发生过程中卵母细胞凋亡的现象、凋亡的分子机理等,同时还探讨了卵母细胞凋亡的途径。     

哺乳动物卵母细胞凋亡的研究现状及新进展

细胞凋亡又称程序性细胞死亡,是指机体为维持体内环境的稳定,由基因控制的细胞自主的有序性死亡。对于雌性生殖系而言,细胞凋亡是维持其正常功能的一个重要组成要术。就哺乳动物来说,超过99．9％的雌性生殖细胞会在发育的不同时期发生凋亡。本文主要综述了细胞凋亡的新概念、卵子发生过程中的细胞凋亡现象,同时还对当今卵母细胞凋亡研究的现状及新进展做出了总结。     

Fas/FasL系统调控公牛精子发生的研究进展

牛的精子发生是一个特殊的雄性生殖细胞的分化、增殖和凋亡的过程。在这一过程中,生殖细胞总是不断地处于分化和凋亡的动态平衡之中。凋亡信号转导分子Fas和FasL组成的Fas/FasL系统不但在细胞自稳和疾病发生中具有重要作用,而且参与调控牛的精子发生。当Fas和FasL表达异常时,直接影响生殖细胞的发育和增殖。作者通过阐明Fas/FasL系统在牛精子发生过程中的调控机理,为提高种公牛的繁殖性能开创一条新的途径。     

Pathogenesis of type 1 (European genotype) porcine reproductive and respiratory syndrome virus in male gonads of infected boar

The objective of this study was to determine the pathogenesis of experimental infection with a type 1 porcine reproductive and respiratory syndrome virus (PRRSV) by defining the sites of viral replication and apoptosis in male gonads from infected boars for a period of 21 days after intranasal inoculation. Microscopically, hypospermatogenesis and abundant germ cell depletion and death were observed in the testes. Such germ cell death occurs by apoptosis, as determined by a characteristic histological patterns and evidence of massive DNA fragment detected in situ terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) reaction. PRRSV was detected in the testicular tissue of infected boars only. Viral nucleic acid was localized in spermatogonia, spermatocytes and spermatids but not in the vesicular and bulbourethral gland. In serial sections, PRRSV-positive cells did not co-localized with apoptotic cells. TUNEL-positive apoptotic cells were more numerous than PRRSV-positive cells in testicular sections. The present study demonstrated that type 1 PRRSV infects the spermatogonia and their progeny, and induces apoptosis in these germ cells.     

Effects of 17beta-estradiol,bisphenol A and tributyltin chloride on germ cells of Caenorhabditis elegans

Effects of a one-generation exposure to a natural estrogen, 17beta-estradiol (E2), and environmental pollutants such as bisphenol A (BPA) and tributyltin chloride (TBTCL) on the number of germ cells were investigated in the hermaphrodite Caenorhabditis elegans. The eggs of gravid adult worms isolated by alkaline hypochlorite treatment were seeded on a test chemical-containing NGM (nematode growth medium) agar plate without cholesterol. After incubation for 6 days at 16 degrees C, the germ cells of adult worms were stained with 4', 6-diamino-2-phenylindole dihydrochloride (DAPI). The staining procedure was completed within one hour and the stained germ cells were counted under a fluorescence microscope without dissection. The number of germ cells in the worms treated with E2 (10(-10)-10(-6) M) and BPA (10(-9)-10 (-5) M) was significantly increased. Maximal increases were observed at 10(-8) M E2 (156 +/- 15.3% of control) and 10(-5) M BPA (168 +/- 20.0 % of control). TBTCL (10(-9)-10(-6) M) significantly decreased the number of germ cells. The minimal decrease was observed at 10(-6) M TBTCL (30.2 +/- 3.51% of control). These results indicate that changes in the number of germ cells are a sensitive indicator of the effects of chemicals on the reproductive system. Since the method described in this paper is a novel, simple, time- and money-saving bioassay, C. elegans is an excellent model with which to determine the reproductive toxicity of chemicals including environmental pollutants.     

羊驼睾丸细胞凋亡及凋亡相关蛋白的定位

本研究旨在观察羊驼睾丸的出生后发育和精子发生过程中的细胞凋亡及凋亡相关蛋白Bcl2和Caspase3 的定位.取材新生、12月龄和24月龄羊驼的睾丸,用TUNEL法检测睾丸发育和精子发生过程的细胞凋亡,用免疫组织化学技术检测凋亡相关蛋白Bcl2和Caspase3在羊驼出生后发育和精子发生过程中的定位.结果显示在新生羊驼睾丸未检测到TUNEL阳性细胞,Caspase3和Bcl2表达于间质细胞,提示在新生期凋亡蛋白参与间质细胞凋亡的调节,为曲精小管的发育提供空间;12月龄羊驼睾丸TUNEL阳性细胞定位于曲精小管中央部分,Caspase3 和Bcl2定位于间质细胞和曲精小管中央生殖细胞,提示在青春期(12月龄)羊驼睾丸,细胞凋亡和凋亡相关蛋白参与曲精小管管腔形成的调节;24月龄羊驼睾丸TUNEL阳性细胞定位于精原细胞、精母细胞和精子细胞,Caspase3 和Bcl2定位于间质细胞和各个发育阶段的生精细胞,Caspase3阳性细胞在精原细胞最高,向精母细胞和精子细胞逐渐减少,Bcl2在精原细胞弱阳性表达,在血睾屏障以内的曲精小管近腔室部分呈弥散性强阳性表达,提示在性成熟(24月龄)羊驼睾丸精子发生过程中,细胞凋亡主要发生于精原细胞和早期精母细胞,Bcl2可能抑制精母细胞之后生殖细胞的凋亡.结果提示在羊驼睾丸出生后发育和精子发生过程中存在细胞凋亡现象;凋亡蛋白Caspase3和Bcl2参与羊驼睾丸发育和精子发生过程中细胞凋亡的调节.     

SMAD3基因在畜牧生产中的应用研究进展

SMAD3基因是SMADS基因家族成员之一,其编码的SMAD3蛋白是转化生长因子-β(TGF-β)超家族特异的细胞内信号转导分子,SMAD3基因通过TGF-β超家族参与疾病、免疫调节、生长发育、创伤愈合、软骨与骨骼的发育及维持等重要的生理过程,同时还参与调节生殖细胞的增殖、分化、成熟、黏附、闭锁、凋亡和甾体激素的产生等,因此,了解SMAD3基因的结构与功能对动物生长发育、繁殖等研究具有重要意义。文章简述了SMAD3基因结构、功能、作用机理,分析了其在畜牧生产方面相关的应用研究进展发现,目前SMAD3基因在畜牧生产上的应用研究主要集中在参与调控脊椎动物(猪、牛、羊、鸡等)生长、发育、细胞免疫与凋亡、激素分泌及繁殖功能方面;SMAD3基因在调控动物机体疾病发生、生长发育、脂肪沉积及繁殖性能方面仍是国内外研究的热点,而该基因对畜禽疾病发生、生长和繁殖性能的精确分子调控机制仍有待进一步研究。     

Expression of p63 in the mouse primordial germ cells

Proteins encoded by p63 gene a have structural similarity with tumor suppressor p53, and were thought to induce cell cycle arrest and apoptosis during development. The p63 proteins are also expressed in the basal cells of many epithelial tissues in the adult, and supposed to play important roles in maintaining the epidermal stem cells. Previously, we reported the p63 expression in the testis of mouse embryos, suggesting their involvement in the growth arrest and apoptosis of testicular germ cells (Nakamuta and Kobayashi, J. Vet. Med. Sci. 65:853-856). In this study, we investigated the timing of this p63 expression in the germ cells during migration and colonization to the gonads. Immunohistochemical analysis of mice from embryonic day (E) 7.5 to E12.5 demonstrated that p63 positive reactivity was seen as early as E8.5 when the founder cells of germ cells, primordial germ cells (PGCs), were located in the hind gut epithelium, but PGCs were negative for p63 at E7.5 when they first appeared. p63 is expressed as six isoforms, resulting from alternative splicing at C-terminus and by the use of two promoters that generate variations at N-terminal end. RT-PCR analyses suggested that different types of p63 mRNAs were likely to be expressed in PGCs during development. These results imply that p63 may be involved in the regulation of PGC development by controlling the gene expression required for their migration and colonization to the gonads.     

Effects of luteinizing hormone treatment on oogenesis in ovarian germ cells of the chick (Gallus domesticus)

The effect of the luteinizing hormone (LH) on the oogenesis of ovaries from newly-hatched chicks treated in vivo on days 13, 15, and 17 of embryonic development was analyzed. Changes in oogonial proliferation, meiotic prophase, degeneration of germ cells, and primordial follicular organization were determined. Results indicate that the total number of germ cells was not affected by the LH treatment, but significant differences existed in the number of oogonia and oocytes between the ovaries of control and LH-treated chicks. LH treatment increased the percentage of oocytes and diminished the percentage of oogonia. The mitotic activity of oogonia and degeneration of germ cells decreased, but the number of follicles during development increased in LH-treated ovaries. These findings suggest that LH treatment might trigger a cascade of endocrine events, resulting in inhibition of oogonial proliferation and induction of the meiotic prophase and follicle formation.