共查询到20条相似文献,搜索用时 15 毫秒
1.
TAKEO KISHIMOTO MICHIYASU YOSHIKUNI HIROYUKI IKADAI HARUO KANATANI 《Development, growth & differentiation》1985,27(3):233-242
Effect of tumor promoters including phorbol esters and teleocidin on 1-methyladenine (1-MeAde)-induced oocyte maturation was studied in the starfish. When isolated immature oocytes were treated with 1-MeAde and 12-O-tetradecanoylphorbol-13-acetate (TPA), 1-MeAde-induced maturation was completely inhibited at more than 2.5 μg/ml. However, if TPA was added after the hormone-dependent period (the minimum period wherein 1-MeAde is required), such maturation-inhibiting effect was no longer observed. Pretreatment with TPA for 5 min showed that its inhibitory action is irreversible. However, when TPA-injected oocytes were treated with 1-MeAde, all oocytes underwent germinal vesicle breakdown (GVBD). GVBD was induced in TPA-treated oocytes upon injection of the cytoplasm of maturing oocytes containing maturation-promoting factor (MPF). These facts show that TPA acts on the oocyte surface to inhibit the production of MPF. Retinoids including retinal, retinol and retinoic acid reversed the inhibitory effect of TPA on 1-MeAde-induced maturation. Experiments with various phorbol esters showed a good correlation between their maturation-inhibiting activity and their known tumor-promoting activity. Further, telecoidin, which is structurally unrelated to phorbol esters, inhibited 1-MeAde action. Since both tumor-promoting phorbol esters and teleocidin are known to activate Ca2+ -activated, phospholipid-dependent protein kinase (protein kinase C) and their activation effect is inhibited by retinoids, it appears that the activation of protein kinase C by tumor promoters is involved in blocking of 1-MeAde action. 相似文献
2.
Oocyte Maturation in Starfish: Sequential Changes of Oocyte Shape Induced by 1-Methyladenine Associated with Germinal Vesicle Breakdown 总被引:4,自引:4,他引:0
Observation of the early events of starfish oocyte maturation revealed a sequential change of the oocyte shape induced by 1-methyladenine (1-MeAde). The lengths of two diameters of the whole oocyte, one parallel to the egg axis (a–v diameter) and the other which is perpendicular to a–v diameter (e diameter) were measured by taking photographs successively. About 10 min after 1–MeAde administration, a sudden decrease of the a–v diameter (shortening of oocyte) occurred followed by a sudden increase (elongation of oocyte). Germinal vesicle breakdown (GVBD) occurred when the a–v diameter suddenly increased. The change of the oocyte shape occurred differentially in the animal and vegital halves i.e. when the egg-axis diameter shortened the surface of the vegital pole side shrank and the surface of the animal pole side expanded. GVBD was suppressed under hypertonic conditions and facilitated under hypotonic conditions. Cytological examination of the process of GVBD revealed (1) separation of the nuclear membrane from the granular cytoplasmic mass, (2) depression of several parts of the nuclear membrane and the increase of amorphous matrix on the outside of the nuclear membrane, and (3) disappearance (fragmentation) of nuclear membrane. The morphological changes were not the same along the egg-axis temporally and spacially. These observations suggest firstly that the cytoplasm, which has been in a certain quiescent state with a certain rigidity before 1–MeAde administration, not only undergoes a decrease in stiffness but also acquires a contractile property after 1–MeAde administration, and secondly that contractile or cytoskeletal components do not evenly function or are not evenly arranged in the animal and vegital halves. 相似文献
3.
Dynamics of Mitotic Apparatus Formation and Tubulin Content during Oocyte Maturation in Starfish 总被引:2,自引:2,他引:0
Hiroko Shirai Natsumi Hosoya Tomoo Sawada Yoshitaka Nagahama Hideo Mohri 《Development, growth & differentiation》1990,32(5):521-529
To follow the topo-temporal behavior of structures containing tubulin and the change in tubulin content during oocyte maturation, starfish oocytes were extracted with a medium containing detergent so that morphological observation and biochemical analysis could be conducted on the same residual oocyte preparation simultaneously. Before 1-methyladenine (1-MeAde) stimulation, "pre-meiotic asters" were observed on the germinal vesicle at the animal pole. 1-MeAde caused the appearance of distinct asters at the position of the aster precursor. When germinal vesicle breakdown (GVBD) took place, chromosomes were condensed. Chromosome gathering was concurrent with a reduction in the size of nuclear matrix. The mitotic apparatus was first constructed parallel to the cortex and then changed its axis perpendicularly. Fluorescence of tubulin due to indirect immunofluorescence in the cytoplasm other than the mitotic apparatus decreased rapidly along the course of maturation at least up to the first metaphase. Despite these dynamic morphological change, the tubulin content in the whole oocyte and the residual structures, measured by SDS-PAGE and immunostaining, did not show remarkable (statistically significant) changes through the course of maturation, although the content tended to decrease a little before the second polar body formation and to increase thereafter in the latter. 相似文献
4.
SHIRLEY A. HULL ALLEN SCHUETZ BRYAN TOOLE 《Differentiation; research in biological diversity》1979,15(1-3):127-132
The in vitro effects of 2-4-dinitrophenol (DNP) on spawning and follicular and oocyte maturation in starfish ovaries and its various cellular components were investigated. Spawning and oocyte and follicular maturation induced by starfish gonadotropin radial nerve factor (RNF) in isolated ovarian fragments were all inhibited by appropriate doses of DNP. DNP inhibits processes which occur shortly after addition of the gonadotropin; in ovarian fragments insensitivity to DNP inhibition occurred shortly after addition of RNF but prior to initiation of spawning. Spontaneous follicular and oocyte maturation which occurred following release of ovarian follicles into sea water was prevented by DNP. In non-spontaneously maturing follicles released from the ovary, DNP inhibited both follicle and oocyte maturation induced by the secondary stimulator of spawning and maturation, 1-methyladenine (1-MA). DNP also inhibited 1-MA induced meiotic maturation in isolated immature oocytes incubated in the absence of follicle cells. Inhibition of oocyte maturation was not associated with inhibition of 3 H-1-MA incorporation by isolated oocytes. Immature oocytes incubated in the presence of DNP underwent maturation following washing and subsequent exposure to 1-MA. Immature oocytes initially exposed to both 1-MA and DNP, however, showed decreased maturation responsiveness following washing and re-exposure to 1-MA. The results suggest that the inhibitory effects of DNP on spawning and oocyte maturation are the result of direct effects on the oocytes and possibly other cells and tissues within the ovary. 相似文献
5.
S. A. J. Daniel M. W. Khalil D. T. Armstrong 《Molecular reproduction and development》1986,13(2):173-184
Recent work has shown that 19-norandrostenedione is a major steroidal component of porcine follicular fluid; however, little is known about its role(s) in the regulation of follicular function. This study was designed to examine the effect of 19-norandrostenedione on porcine oocyte maturation in vitro. Oocyte-cumulus complexes were isolated from medium (3–6-mm diameter)-sized prepubertal pig follicles and incubated for 12 h in medium with or without dibutyryl cyclic AMP ((Bu)2cAMP, 1 mM) with or without testosterone (5 x 10?7 M) or 19-norandrostenedione (5 x 10?7 M). In medium alone, 70.8% of oocytes spontaneously resumed meiosis as evidenced by the occurrence of germinal vesicle breakdown. Oocyte maturation was inhibited by (Bu)2cAMP (44.6% of oocytes matured). Although neither steroid alone affected maturation, both testosterone and 19-norandrostenedione enhanced the effect of (Bu)2cAMP (22.5 and 19.6%, respectively, resumed meiosis). The effects of testosterone and 19-norandrostenedione on (Bu)2cAMP-inhibited oocyte maturation were dose dependent and there was no significant difference between the actions of the steroids. The effect of 19-norandrostenedione was reversible and dependent on the presence of an intact cumulus. Hydroxyflutamide (SCH-16423), a nonsteroidal compound known to block androgen receptors, abolished the effects of both testosterone and 19-norandrostenedione on germinal vesicle breakdown, indicating that the actions of these steroids are truly androgenic. The results of this study suggest that 19-norandrostenedione may be of physiological importance in the regulation of porcine oocyte maturation. 相似文献
6.
Chronological changes of bovine follicular cumulus-oocyte-complexesi were studied after in vitro maturation over a period of 48 h. According to their thickness and compactness of cumulus investments they were classified into 4 groups and cultured in enriched Ham’s F-10 medium with or without human chorionic gonadotrophin (hCG) and estradiolbenzoate (EB) for 0, 6, 12, 18, 21, 24, 27, 30 and 48 h. Representative samples were taken at each time interval for evaluation of nuclear maturation stages, ooplasm quality and size of the peri vitelline space (PVS). The results showed that oocyte nuclear breakdown (ONBD) required 6 to 12 h culture, and the peak of the first polar abstriction occurred at 24 h. The culture period required for ONBD and abstraction of the first polar body were related to the thickness and compactness of cumulus investments with and approximately 6 h delay in heavily compacted complexes. Ooplasm quality evaluation failed to show a clear trend, but the PVS increased in size from 0 h to 30 h and then, retracted again from 30 to 48 h. The overall maturation rate in the presence of hCG and EB was 79.1 %, and a substantial proportion (68.8 %) of nude or partially covered oocytes reached metaphase II stage. In the presence of hCG and EB no block at either metaphase I or at anaphase-telophase I was observed. In the absence of hCG and EB the percentage of oocytes reaching metaphase II was much lower (48.6%) in comparison with oocytes matured in the presence of these hormones (79.1 %). It was concluded a very high proportion of slaughterhouse oocytes could be matured in vitro and that the cumulus investments and addition of certain hormones affected the maturation rate. 相似文献
7.
Jon Romero-Aguirregomezcorta ángela Patricia Santa Francisco Alberto García-Vázquez Pilar Coy Carmen Matás 《PloS one》2014,9(12)
Nitric oxide (NO) is a molecule involved in many reproductive processes. Its importance during oocyte in vitro maturation (IVM) has been demonstrated in various species although sometimes with contradictory results. The objective of this study was to determine the effect of NO during IVM of cumulus oocyte complexes and its subsequent impact on gamete interaction in porcine species. For this purpose, IVM media were supplemented with three NOS inhibitors: NG-nitro-L-arginine methyl ester (L-NAME), NG-monomethyl-L-arginine (L-NMMA) and aminoguanidine (AG). A NO donor, S-nitrosoglutathione (GSNO), was also used. The effects on the cumulus cell expansion, meiotic resumption, zona pellucida digestion time (ZPdt) and, finally, on in vitro fertilization (IVF) parameters were evaluated. The oocyte S-nitrosoproteins were also studied by in situ nitrosylation. The results showed that after 42 h of IVM, AG, L-NAME and L-NMMA had an inhibitory effect on cumulus cell expansion. Meiotic resumption was suppressed only when AG was added, with 78.7% of the oocytes arrested at the germinal vesicle state (P<0.05). Supplementation of the IVM medium with NOS inhibitors or NO donor did not enhance the efficiency of IVF, but revealed the importance of NO in maturation and subsequent fertilization. Furthermore, protein S-nitrosylation is reported for the first time as a pathway through which NO exerts its effect on porcine IVM; therefore, it would be important to determine which proteins are nitrosylated in the oocyte and their functions, in order to throw light on the mechanism of action of NO in oocyte maturation and subsequent fertilization. 相似文献
8.
Cytoplasmic Maturity Revealed by the Structural Changes in Incorporated Spermatozoon during the Course of Starfish Oocyte Maturation 总被引:4,自引:4,他引:0
SETSURO HIRAI YOSHITAKA NAGAHAMA TAKEO KISHIMOTO HARUO KANATANI 《Development, growth & differentiation》1981,23(5):465-478
Immature oocytes of the starfish, Asterina pectinifera, are polyspermic. Spermatozoa can enter immature oocytes upon insemination, but the changes associated with the fertilization process in oocytes matured with 1-methyladenine (1-MeAde), such as the formation of aster and pronucleus, were not observed. After immature oocytes, previously inseminated, were matured with 1-MeAde, the formation of the sperm monaster was observed during germinal vesicle breakdown (GVBD). Amphiasters and pronuclei were formed after the formation of the second polar body. The acquisition by oocytes of the capacity to undergo the normal process of fertilization, therefore, occurs during the course of oocyte maturation. After injection of the cytoplasm of maturing oocytes into inseminated immature oocytes, the formation of aster and pronucleus was observed, suggesting that maturation-promoting factor (MPF) may be involved in establishing the cytoplasmic conditions (cytoplasmic maturity) necessary for the fertilization process to occur. In contrast, when enucleated, inseminated halves of immature oocytes were treated with 1-MeAde, only monasters were formed, while in the nucleated halves both amphiasters and sperm pronuclei were formed. Thus, germinal vesicle material is required for the formation of amphiaster and sperm pronucleus but not for the formation of monaster. It is possible that the amount of MPF produced in enucleated halves was sufficient only for the formation of the monaster but not for the formation of the amphiaster and pronucleus, since it has been previously established that germinal vesicle material is necessary for the amplification of MPF. The formation of the monaster in the enucleated halves at a time corresponding to GVBD in nucleated controls suggests that the amount of MPF needed for this event is rather small. For the induction of subsequent fertilization process, large amounts of MPF may be required to establish the necessary cytoplasmic conditions, although other possible role of nuclear material is not excluded. 相似文献
9.
山羊卵母细胞体外成熟过程中线粒体的动态分布 总被引:2,自引:0,他引:2
目的研究山羊卵母细胞减数分裂过程中线粒体的动态分布。方法收集山羊卵母细胞,在M199中分别培养4、8、12、16、20和24 h,用特异性线粒体标记探针进行标记,用激光扫描共聚焦显微镜观察线粒体的分布情况。结果生发泡期线粒体多分散在卵母细胞的胞质内,并且距生发泡有一定的距离;生发泡破裂期线粒体逐渐移向染色质;第一次减数分裂中期与第二次减数分裂中期线粒体成簇密布在染色体周围。排出的第一极体中也含有大量的线粒体。结论同其他哺乳动物卵母细胞体外成熟过程中线粒体分布情况相比,线粒体在山羊卵母细胞中的分布具有明显的相似性。线粒体密布在成熟卵母细胞染色体周围可能与极体的排出和受精后染色体的迁移有关。 相似文献
11.
Setsuko K. Satoh Mikako T. Oka Yukihisa Hamaguchi 《Development, growth & differentiation》1994,36(6):557-565
In order to study the dynamic behavior of the mitotic apparatus leading to unequal cleavage, we investigated the distribution of mitotic microtubules (MTs) during maturation division of starfish oocytes. When the mitotic apparatus attached to the cell surface at metaphase, in both the first and second meiotic division, it is revealed, by immunofluorescence, that the MT distribution in the spindle, as well as in the aster, became asymmetric. MTs in the peripheral half spindle increased in number compared with those in the inner half spindle. Furthermore, these results were confirmed in the living cell by polarization microscopy; shortly after the attachment, the birefringence retardation of the peripheral half spindle became greater than that of the inner one, and the difference increased with time during anaphase. By inhibiting the attachment of the mitotic apparatus by means of centrifugation, the MT distribution maintained a symmetrical pattern through mitosis. These results suggest that the attachment of the mitotic apparatus to the cell surface induces the asymmetrical distribution of MTs not only in the aster but also in the spindle. Such a rich distribution of MTs in the peripheral half spindle appears to ensure chromosome exclusion into the polar body by anchoring them firmly to the cell surface of the animal pole. 相似文献
12.
Keiju Okano Nobuhiko Ohkawa Susumu Ikegami 《Bioscience, biotechnology, and biochemistry》2013,77(9):2823-2826
The ovary of the starfish Asterias amurensis contains various kinds of steroidal saponins. The structure of one of the major saponins, designated ovarian asterosaponin-4, was elucidated by several chemical modifications and spectroscopic analyses. The structure was formulated as 20α -hydroxy-6 α -O-{6-deoxy-β -D-glucopyranosyl(1→2)- β -D-glucopyranosyl(1→4)-[6-deoxy- β -D-glucopyranosyl (1→2)]- β -D-xylopyranosyl(1→3)-6-deoxy->β-D-gluco-pyranosyl}-3β-sulfo-oxy-5α -cholesta-9(11), 24-diene. Ovarian asterosaponin-4 at 125μg/ml inhibited spontaneous oocyte maturation of the starfish, and the inhibition could be overcome by adding 1 × 10?6M of 1-methyladenine, the maturation-inducing substance of the starfishes, to the oocyte. 相似文献
13.
Yueshuai Guo Lingbo Cai Xiaofei Liu Long Ma Hao Zhang Bing Wang Yaling Qi Jiayin Liu Feiyang Diao Jiahao Sha Xuejiang Guo 《Molecular & cellular proteomics : MCP》2022,21(8):100267
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14.
DNA Synthesis during Maturation of Starfish Oocytes 总被引:1,自引:0,他引:1
IN Xenopus, nuclear DNA is replicated at an early stage of meiosis and there is no measurable DNA synthesis during the long diplotene stage characterized by the presence of the lampbrush chromosomes1–3; this is probably a general phenomenon in animals. But in the case of pollen formation in plants, autoradiographic data suggest that, in addition to normal replication during S phase, some chromosomal DNA is synthesized throughout meiosis4. Limited DNA synthesis also follows replication during the S phase in Lilium anthers5. 相似文献
15.
小鼠卵母细胞体外成熟、体外受精的效果观察 总被引:2,自引:0,他引:2
目的 研究不同培养条件对小鼠卵母细胞体外成熟及体外受精率的影响。方法 小鼠卵母细胞分别在含有FSH、BSA和胰岛素的培养液中体外成熟,在Whitten 氏液中体外受精,比较体外成熟率、体外受精率。结果 1- 裸卵(DO) 的体外成熟率、体外受精率(81-4% ,31-0 % ) 均高于卵丘卵母细胞复合体(COC)(48-6 % ,27-1% ) 。2- 在培养液中添加FSH、胰岛素和BSA,卵母细胞的体外成熟率为77-9 % ,82-3% 、60-7% ;体外受精率为77-2 % 、72-6 % 、26-7% ;2 - 细胞率为49-2 % 、34-2 % 、10-0% 。胰岛素组的卵母细胞IVM 率最高,但IVF率、2 - 细胞率低于FSH 组。3- 添加BSA的两组的体外受精率只有26-7 % 、25-8 % ,显著低于其他组,其体外成熟率也较添加FSH 和胰岛素的组成。4- 排出第一极体(PbI) 的卵母细胞的体外受精率和2 - 细胞率(85-9 % ,22-4% ) 均高于GV期卵母细胞(71-1 % ,12-9 % ) 。结论 1- 卵丘卵母细胞(COC) 较裸卵(DO) 的体外成熟率、体外受精率都低,差异显著(P成熟< 0-01;P受精< 0-05) 。2-FSH 和胰岛素均能提高小鼠卵母细胞的体外成熟率、体外受精率。3-BSA可以降低小鼠卵母细胞体外受精率,差异极显著。4-GV 期卵母细胞的体外受精率显著低于体外培养的排出第一极体的卵母细胞(P2 - cell < 0-05,P受精<0-05) 相似文献
16.
The temporal sequence of development of lymphocystis disease virus (LDV) was studied by electron microscopy of thin sections of infected tissue-culture monolayers. Neither the typical cytoplasmic inclusion nor virus was detected at 4 days postinfection (PI). Inclusions, but no viruses, were detected at 8 days PI. Inclusions and associated virions were detected at 15 days PI, and by 28 days PI the undisrupted cells were filled with the typical virions. No release mechanism was detected, and severe clumping of particles was noted. Negatively stained preparations revealed particles 200 nm in diameter with no capsomere structure and apparent spikes associated with the particle. The relationship of LDV to the well-defined deoxyribonucleic acid virus groups is discussed. 相似文献
17.
THOMAS E. SCHROEDER 《Development, growth & differentiation》1985,27(3):311-321
The animal-vegetal (A-V) axis in oocytes of the starfish Pisaster ochraceus and Asterina pectinifera is described in terms of new cytological observations. Ordinarily, this axis of polarity is revealed by the eccentric germinal vesicle that is displaced toward the animal pole where polar bodies eventually form. In addition, however, the cortex at the animal pole is characterized by a pre-meiotic aster (centrosomes and bundles of microtubules lying within folds of the nuclear envelope), an absence of large, so-called “acidic vacuoles” that occur abundantly everywhere else, a diminished ability to form actin-filled spikes, and local mechanical weakness. These expressions of the A-V axis within the cortex are documented by micrographs. The problem of distinguishing if any feature is an “expression” or a “determinant” of axial differentiation is briefly discussed. 相似文献
18.
Immature Glycine max (L.) Merr. seeds initially at 5070mg fresh weight were successfully grown and matured in vitroin detached pods. Surface sterilized pods were floated in aliquid medium containing 5 per cent sucrose, minerals, and glutaminein 125 ml Erlenmeyer flasks and incubated at 25 °C under350400 µE m1 s1 white light. Seedswhich were matured in vitro increased tenfold in dry weight,were visually similar to commercial seeds of the same size,were tolerant to desiccation and germinated with normal seedlinggrowth. Excised pods transported dye from the pedicel to thegrowing seed within 120 min. Soya bean pod culture is a usefultechnique to study the influence of single or combinations ofchemical or environmental parameters on regulation of seed growth,seed maturation, and subsequent germination events without theconfounding interactions with the mother plant. Glycine max (L.) Merr., soya bean, pod culture, seed culture, seed growth, seed maturation, germination 相似文献
19.
ShuZhen Liu LiGang Jiang XiaoQian Meng XiaoYing Han Dong Cheng TianLiang Zhang YiLiang Miao 《PloS one》2014,9(7)
Polychlorinated biphenyls (PCBs) are stable, lipophilic compounds that accumulate in the environment and in the food chain. Though some studies provided evidence that PCBs had adverse effects on reproductive function, most of these results were from in vitro models. Therefore we investigated the effect of Aroclor 1254 (a commercial PCBs mixture) treatments on in vivo maturation and developmental potential of mouse oocytes. In the present study, female ICR mice were treated with different doses (12.5, 25 and 50 mg/kg) of Aroclor 1254 (a commercial PCB mixture) once every 72 hours by intraperitoneal injection for 9 days. After three treatments of Aroclor 1254, the mice were superovulated to collect oocytes one day after the last exposure. The effects of Aroclor 1254 on oocyte maturation, fertilization, and preimplantation embryonic development were investigated. Immunofluorescence-stained oocytes were observed under a confocal microscope to assess the effects of Aroclor 1254 on spindle morphology. Parthenogenic activation and the incidence of cumulus apoptosis in cumulus-oocyte complexes were observed as well. Oocytes exposed to different doses of Aroclor 1254 in vivo were associated with a significant decrease in outgrowth potential, abnormal spindle configurations, and the inhibition of parthenogenetic activation of ovulated oocytes. Furthermore, the incidence of apoptosis in cumulus cells was increased after exposed to Aroclor 1254. These results may provide reference for the treatment of reproductive diseases such as infertility or miscarriage caused by environmental contaminants. 相似文献
20.
Cysteine: Depolarization-Induced Release from Rat Brain In Vitro 总被引:3,自引:2,他引:1
Hans Jörg Keller Kim Quang Do Markus Zollinger Kaspar H. Winterhalter Michel Cuénod 《Journal of neurochemistry》1989,52(6):1801-1806
Compounds released on depolarization in a Ca2+-dependent manner from rat brain slices were screened to identify candidates for neuroactive substances. Lyophilized superfusates were analyzed by reversed-phase HPLC after derivatization with 9-fluorenyl N-succinimidyl carbonate. One of the compounds that showed an increase of concentration in superfusates in the presence of iodoacetamide was identified as the cysteine (Cys) derivative, S-carboxamidomethylcysteine, by fast atom bombardment mass spectrometry and other methods. This stable Cys derivative originates from endogenous, extracellular Cys. The finding led to a method for quantification of Cys in superfusates by immediate cooling of the superfusates to 0 degrees C and reaction of Cys with N-ethylmaleimide. Depolarization-induced Ca2+-dependent release of Cys was most prominent in the neocortex, followed by the mesodiencephalon, striatum, and cerebellum. This suggests that Cys is released from a neuronal compartment and might be involved in neurotransmission. 相似文献