Reviews of reproduction最新文献_第8页

Protein kinase C action at fertilization: overstated or undervalued? 蛋白激酶C在受精中的作用:被高估还是被低估?

Reviews of reproduction Pub Date : 1998-01-01 DOI: 10.1530/ror.0.0030007

K T Jones

{"title":"Protein kinase C action at fertilization: overstated or undervalued?","authors":"K T Jones","doi":"10.1530/ror.0.0030007","DOIUrl":"https://doi.org/10.1530/ror.0.0030007","url":null,"abstract":"At fertilization, the spermatozoon is generally held to generate two important second messengers, inositol trisphosphate and diacylglycerol. A similar situation arises when these signalling molecules are generated after a hormone binds to its plasma membrane receptor. This signalling mechanism releases intracellular Ca2+ which causes cortical granule release and initiates meiotic resumption. This review will examine the role played at fertilization by protein kinase C which is a primary target of diacylglycerol. The pharmacological agents phorbol esters, which mimic the action of diacylglycerol, when added to mammalian oocytes induce cortical granule release and may cause meiotic resumption. However, the originally accepted mechanism of fertilization is now questioned with the recent finding of a soluble sperm Ca2+-releasing factor expelled directly into the oocyte cytoplasm, bypassing any membrane receptor. Therefore, it is timely to re-evaluate the role played by protein kinase C at fertilization in light of a mechanism that may produce Ca2+ without producing diacylglycerol concomitantly. This article will examine the evidence implicating activation of protein kinase C in Ca2+ oscillations, cortical granule release and meiotic resumption. It will contend that pharmacological studies relying on the specificity of phorbol esters and other agonists, as well as inhibitors of protein kinase C, have produced conflicting interpretations of the role of this kinase at fertilization.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"3 1","pages":"7-12"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0030007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20432847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 47

Pepsin-related molecules secreted by trophoblast. 滋养细胞分泌的胃蛋白酶相关分子。

Reviews of reproduction Pub Date : 1998-01-01 DOI: 10.1530/ror.0.0030062

J A Green, S Xie, R M Roberts

{"title":"Pepsin-related molecules secreted by trophoblast.","authors":"J A Green, S Xie, R M Roberts","doi":"10.1530/ror.0.0030062","DOIUrl":"https://doi.org/10.1530/ror.0.0030062","url":null,"abstract":"The pregnancy-associated glycoproteins (PAGs) were first described as placental antigens of cattle that were also present in the blood serum of the mother after implantation. Molecular cloning studies have shown that they are members of the aspartic proteinase gene family and closely related to the pepsinogens. An enzymatic role seems unlikely, as at least some of them have mutations likely to render them enzymatically inactive. Nevertheless, these molecules have retained the substrate-binding cleft of the pepsins and are expressed abundantly in trophectoderm, particularly in the invasive binucleate cell component. There may be as many as 100 PAG genes in cattle and sheep, many of which are transcribed. PAGs are also products of the placenta of the pig, a species whose progenitors diverged from the ruminants at least 55 million years ago. There is even evidence for PAG-like molecules outside the Artiodactyla. Although their function remains elusive, it seems unlikely that these placentally expressed molecules are simply oddities in view of their long-term evolutionary survival and conspicuous presence at the fetal-maternal interface.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"3 1","pages":"62-9"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0030062","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20433350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 70

Transforming growth factor beta and the endometrium. 转化生长因子和子宫内膜。

Reviews of reproduction Pub Date : 1998-01-01 DOI: 10.1530/ror.0.0030001

J D Godkin, J J Doré

{"title":"Transforming growth factor beta and the endometrium.","authors":"J D Godkin, J J Doré","doi":"10.1530/ror.0.0030001","DOIUrl":"https://doi.org/10.1530/ror.0.0030001","url":null,"abstract":"During the oestrous or menstrual cycle and throughout much of pregnancy, the uterine endometrium undergoes rapid, as well as progressive, morphological and functional modification. During the preimplantation stage of pregnancy, the endometrium provides an environment that sustains embryonic development, and then participates in the nidation process. Later, the endometrium contributes the maternal component of the fetomaternal placenta. For a successful pregnancy, the placenta must orchestrate and regulate opposing forces. Trophoblast invasion must be limited to protect the uterus from destruction, while the allogenic fetus must be guarded from maternal immunological attack. Because of their powerful effects on the cellular and molecular processes associated with cellular proliferation and differentiation, angiogenesis and immunomodulation, the transforming growth factor beta (TGF-beta) polypeptides have been identified as potential modulators of many endometrial functions. Here, we examine the literature concerning cell-specific and temporal patterns of TGF-beta expression in the uterine endometrium during the oestrous cycle and pregnancy and evaluate the influence of ovarian steroids on TGF-beta expression in a range of species. Studies of the function of TGF-beta in the endometrium and at the fetomaternal interface are reviewed and discussed.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"3 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0030001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20432846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 113

Steroid control of monoamines in relation to sexual behaviour. 甾体控制单胺类与性行为的关系。

Reviews of reproduction Pub Date : 1998-01-01 DOI: 10.1530/ror.0.0030031

C Fabre-Nys

引用次数: 44

Host and viral factors influencing heterosexual HIV transmission. 影响异性恋HIV传播的宿主和病毒因素。

Reviews of reproduction Pub Date : 1998-01-01 DOI: 10.1530/ror.0.0030042

C J Miller

{"title":"Host and viral factors influencing heterosexual HIV transmission.","authors":"C J Miller","doi":"10.1530/ror.0.0030042","DOIUrl":"https://doi.org/10.1530/ror.0.0030042","url":null,"abstract":"The World Health Organization estimates that 28-30 million people have been infected with human immunodeficiency virus (HIV). Although many important questions remain, much has been learned regarding the biology of heterosexual HIV transmission. For example, most sexual transmission of HIV is probably mediated by cell-free virus. Langerhans cells in the vaginal epithelium and dendritic cells or macrophages in the lamina propria are the most likely target cells in HIV transmission. Although there is restriction in the genotypes of viruses that are sexually transmitted, the common phenotypic characteristic of these viruses does not appear to be related to in vitro measures of tropism but rather to the relatively high in vivo replicative fitness of the transmitted viral variants. Clearly, host factors such as the amount of HIV-1 co-receptor expression on host cells and the presence of ulcerative sexually transmitted diseases affect the susceptibility of an individual to HIV infection. The growing body of information has increased the likelihood that a vaccine capable of preventing HIV-1 infection after exposure during sexual activity will be developed in the foreseeable future.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"3 1","pages":"42-51"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0030042","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20433348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

Ovarian follicular dominance: the role of intraovarian growth factors and novel proteins. 卵巢卵泡优势:卵巢内生长因子和新蛋白的作用。

Reviews of reproduction Pub Date : 1997-09-01 DOI: 10.1530/ror.0.0020139

D G Armstrong, R Webb

{"title":"Ovarian follicular dominance: the role of intraovarian growth factors and novel proteins.","authors":"D G Armstrong, R Webb","doi":"10.1530/ror.0.0020139","DOIUrl":"https://doi.org/10.1530/ror.0.0020139","url":null,"abstract":"Folliculogenesis is associated with the development of a group of follicles at various stages of maturation from which a species-specific number of follicles are selected for continued growth. These selected follicles, after being exposed to the requisite hormonal environment, ovulate in response to the preovulatory gonadotrophin surge. Follicular dominance is the mechanism by which the selected follicle(s) undergoes rapid development in an environment where growth and development of other follicles, recruited at a similar time, are suppressed. These processes are controlled by the interaction of endocrine signals and locally produced ovarian growth factors. The response of the two major follicular cell types, granulosa and theca cells, to gonadotrophins is regulated by the local production of growth factors. Mechanisms controlling growth factor action occupy a central role in the regulation of folliculogenesis. In this review, we highlight the influence of the extracellular matrix in this process by describing its involvement in regulating the activity of components of the insulin-like growth factor system, transforming growth factor beta superfamily, fibroblast growth factors and the epidermal growth factor/transforming growth factor alpha family. In addition, some recent studies on the role of protein factors produced by the dominant follicle in maintaining dominance and inhibiting the growth of subordinate follicles are described.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"2 3","pages":"139-46"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0020139","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20343053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 198

Biology of the relaxin-like factor (RLF). 松弛素样因子(RLF)的生物学。

Reviews of reproduction Pub Date : 1997-09-01 DOI: 10.1530/ror.0.0020133

R Ivell

引用次数: 58

Models for male infertility: the t haplotypes. 男性不育的模型:t单倍型。

Reviews of reproduction Pub Date : 1997-09-01 DOI: 10.1530/ror.0.0020157

P Olds-Clarke

{"title":"Models for male infertility: the t haplotypes.","authors":"P Olds-Clarke","doi":"10.1530/ror.0.0020157","DOIUrl":"https://doi.org/10.1530/ror.0.0020157","url":null,"abstract":"The t haplotypes are variant alleles of genes in the proximal region of mouse Chromosome 17, linked together by four inversions. While females carrying two t haplotypes are fertile, males are sterile. Their spermatozoa exhibit severe motility defects and are unable to penetrate zona pellucida-free oocytes. Spermatozoa from males carrying one t haplotype (t/+) exhibit mild motility deficits and a delay in penetration of the zona-free oocyte. The inversions of the t haplotypes contain several genes that cause or contribute to male sterility, at least some of which can be identified by analysis of mice carrying Mus spretus-Mus domesticus recombinant Chromosomes 17. The t haplotypes specify a number of sperm biochemical abnormalities, but these have not been related directly to defects in fertilization. In t/+ males, spermatozoa not bearing the t haplotype are defective in fertilization compared with t-bearing spermatozoa. The mechanism causing this is likely to involve haploid gene expression confined to the t-bearing spermatids. Since many genes situated in the region of the t haplotypes have human homologues, an understanding of t haplotype sterility in mice is expected to contribute significantly to our knowledge of the genetic basis for human sperm dysfunction.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"2 3","pages":"157-64"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0020157","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20344395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 52

Reproductive biology of seals. 海豹的生殖生物学。

Reviews of reproduction Pub Date : 1997-09-01 DOI: 10.1530/ror.0.0020175

S Atkinson

{"title":"Reproductive biology of seals.","authors":"S Atkinson","doi":"10.1530/ror.0.0020175","DOIUrl":"https://doi.org/10.1530/ror.0.0020175","url":null,"abstract":"The reproductive biology of seals is fascinating in many aspects. As in most mammals, the time of onset of puberty in seals is variable. Once sexually mature, most but not all seals are seasonally mono-oestrous, with highly synchronized breeding seasons. They have evolved as either terrestrial or aquatic copulators, although a few species mate in a variety of habitats. Their mating strategies are diverse, ranging from serial monogamy to extreme polygyny. Gestation in seals is characterized by an embryonic diapause, which is obligate in most species. Reactivation of the blastocyst is followed by a placental gestation. All species of seal require a terrestrial (including ice floes) habitat for parturition. Lactation differs between the two seal families: phocid seals have an intense period of maternal investment, during which the mothers fast; otariid seals have a prolonged lactation during which intense bouts of suckling are interspersed by days of separation from their pups while the mother forages at sea. Although the anatomy and functional morphology of seals has been well described, less is known of the endocrinology of reproduction. This is due mainly to the logistical difficulties that researchers experience in collecting serial samples from a species that is relatively difficult to handle. This article reviews the basic anatomy and physiology, and our current understanding of the comparative aspects of reproduction in seals. Reproductive behaviours as well as the influences of environmental factors, such as photoperiod, nutrition and xenobiotics, are also discussed.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"2 3","pages":"175-94"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0020175","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20344397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 160

Placental 11 beta-hydroxysteroid dehydrogenase: barrier to maternal glucocorticoids. 胎盘11 β -羟基类固醇脱氢酶:母体糖皮质激素的屏障。

Reviews of reproduction Pub Date : 1997-09-01 DOI: 10.1530/ror.0.0020129

K Yang

{"title":"Placental 11 beta-hydroxysteroid dehydrogenase: barrier to maternal glucocorticoids.","authors":"K Yang","doi":"10.1530/ror.0.0020129","DOIUrl":"https://doi.org/10.1530/ror.0.0020129","url":null,"abstract":"During mammalian pregnancy, the circulating concentration of cortisol (in rodents, corticosterone) in the mother is much higher than that in the fetus. Since the placenta is the only barrier, apart from the uterus, between the mother and her fetus, this gradient in cortisol concentrations suggests that there is a placental barrier preventing maternal cortisol from crossing into the fetus. The intracellular enzyme 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) is an ideal candidate for this barrier because it interconverts cortisol and corticosterone to their inactive metabolites cortisone and 11-dehydrocorticosterone. Indeed, 11 beta-HSD enzyme is expressed in the placenta of humans and a range of other animal species. Moreover, it is well positioned to serve as the barrier since it is localized to the syncytiotrophoblast, the site of maternal-fetal exchange. Given that fetal exposure to excessive amounts of glucocorticoids leads to intrauterine growth retardation, it has been hypothesized that the physiological significance of this placental 11 beta-HSD barrier is to protect the fetus from adverse effects of maternal glucocorticoids.","PeriodicalId":79531,"journal":{"name":"Reviews of reproduction","volume":"2 3","pages":"129-32"},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1530/ror.0.0020129","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20343051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 132