Parthenogenetic development of mouse embryos in vivo

Development ◽  
1973 ◽  
Vol 30 (3) ◽  
pp. 519-545
Author(s):  
Anna Witkowska
Keyword(s):  
Polar Body ◽  
Subsequent Development ◽  
Hormonal Treatment ◽  
Inbred Strains ◽  
Early Cleavage ◽  
Parthenogenetic Development ◽  
Second Polar Body ◽  
First Time

Newly ovulated eggs from CBA-p and CBA-T6T6 inbred strains were activated in situ with an electric shock of 20–50 V. Both spontaneously ovulating females mated with vasectomized males (strain A) and those induced to ovulate and kept apart from males were used. The immediate reaction of eggs was examined 5–7 h after activation and their subsequent development was followed every day up to the 6th day (eggs examined on the 5th and 6th day were tube-locked by a ligature). In spontaneous ovulators the highest yield of activated eggs was obtained following 30 V shock (75%), with a mean for four series (20, 30, 40 and 50 V) of 46·1%. The most common reaction is extrusion of the second polar body (2 PB) and formation of one pronucleus (about 70% of activated eggs). Other types of reaction include: immediate cleavage, suppression of 2 PB with formation of two or, very rarely, one pronucleus. Thus the majority of eggs are potentially haploid. No relationship between the frequency of various types of reaction and the strength of the shock (voltage) was observed. Up to the 3rd day cleavage proceeds at a normal rate and appears to slow down during the 4th day. In spontaneously ovulating females the incidence of blastocysts among developing eggs rises from 3·4% on the 4th day to 52·5% on the 5th day; the corresponding figures for induced ovulations are 10% and 23·6%. Some embryos despite being composed of a large number of cells (40–120) do not undergo cavitation and remain morulae. On the basis of karyological examination of 60 embryos with analysable metaphase plates 60% were classified as haploid, 16·7% as diploid, 1·7% as tetraploid and 21·6% as haploid/diploid mosaics. During early cleavage binucleate blastomeres (a presumed step in regulation from n to 2n) were observed only in eggs from induced ovulations. In embryos developed from spontaneously ovulated eggs n/2n mosaics were observed for the first time on the 5th day. In general, spontaneously ovulated eggs developed better after activation (both in quantitative and qualitative terms) than those obtained following hormonal treatment.

scholarly journals INTEGRINS MEDIATE PLACENTAL EXTRACELLULAR VESICLE TRAFFICKING TO LUNG AND LIVER IN VIVO

2020 ◽  
Author(s):  
Sean L. Nguyen ◽  
Soo Hyun Ahn ◽  
Jacob W. Greenberg ◽  
Benjamin W. Collaer ◽  
Dalen W. Agnew ◽  
...  
Keyword(s):  
Immune Cells ◽  
Extracellular Vesicle ◽  
Dependent Manner ◽  
Cellular Phenotype ◽  
Reporter Mouse ◽  
Membrane Bound ◽  
First Time

ABSTRACTMembrane-bound extracellular vesicles (EVs) mediate intercellular communication in all organisms, and those produced by placental mammals have become increasingly recognized as significant mediators of fetal-maternal communication. Here, we aimed to identify maternal cells targeted by placental EVs and elucidate the mechanisms by which they traffic to these cells. Exogenously administered pregnancy-associated EVs traffic specifically to the lung; further, placental EVs associate with lung interstitial macrophages and liver Kupffer cells in an integrin-dependent manner. Localization of EV to maternal lungs was confirmed in unmanipulated pregnancy using a transgenic reporter mouse model, which also provided in situ and in vitro evidence that fetally-derived EVs, rarely, may cause genetic alteration of maternal cells. These results provide for the first time direct in vivo evidence for targeting of placental EVs to maternal immune cells, and further, evidence that EVs can alter cellular phenotype.

scholarly journals Phasic contractions of rat mesenteric lymphatics increase basal and phasic nitric oxide generation in vivo

2009 ◽  
Vol 297 (4) ◽  
pp. H1319-H1328 ◽  
Author(s):  
H. Glenn Bohlen ◽  
Wei Wang ◽  
Anatoliy Gashev ◽  
Olga Gasheva ◽  
Dave Zawieja
Keyword(s):  
Nitric Oxide ◽  
Relaxation Mechanism ◽  
Lymph Flow ◽  
Lymphatic Endothelium ◽  
Contraction Frequency ◽  
Diastolic Relaxation ◽  
Intravenous Saline ◽  
First Time

Multiple investigators have shown interdependence of lymphatic contractions on nitric oxide (NO) activity by pharmacological and traumatic suppression of endothelial NO synthase (eNOS). We demonstrated that lymphatic diastolic relaxation is particularly sensitive to NO from the lymphatic endothelium. The predicted mechanism is shear forces produced by the lymph flow during phasic pumping, activating eNOS in the lymphatic endothelium to produce NO. We measured [NO] during phasic contractions using microelectrodes on in situ mesenteric lymphatics in anesthetized rats under basal conditions and with an intravenous saline bolus (0.5 ml/100 g) or infusion (0.5 ml·100 g−1·h−1). Under basal conditions, [NO] measured on the tubular portions of the lymphatics was ∼200–250 nM, slightly higher than in the adjacent adipocyte microvasculature, whereas [NO] measured on the lymphatic bulb surface was ∼400 nM. Immunohistochemistry of eNOS in isolated lympathics indicated a much greater expression in the lymph valves and surrounding bulb area than in the tubular regions. During phasic lymphatic contractions, the valve and tubular [NO] increased with each contraction, and during intravenous saline infusion, [NO] increased in proportion to the contraction frequency and, presumably, lymph flow. The partial blockade of eNOS over ∼1 cm length with Nω-nitro-l-arginine methyl ester lowered the [NO]. These in vivo data document for the first time that both valvular and tubular lymphatic segments increase NO generation during each phasic contraction and that [NO] summated with increased contraction frequency. The combined data predict regional variations in eNOS and [NO] in the tubular and valve areas, plus the summated NO responses dependent on contraction frequency provide for a complex relaxation mechanism involving NO.

Development in vitro and in vivo of aggregated parthenogenetic bovine embryos

1995 ◽  
Vol 7 (5) ◽  
pp. 1073 ◽  
Author(s):  
A Boediono ◽  
S Saha ◽  
C Sumantri ◽  
T Suzuki
Keyword(s):  
Cytochalasin B ◽  
Polar Body ◽  
Cleavage Rate ◽  
Development In Vitro ◽  
Second Polar Body ◽  
Bovine Oocytes ◽  
Longitudinal Diameter ◽  
Parthenogenetic Embryos

Mature bovine oocytes were activated with 7% ethanol followed by cytochalasin B or D treatment. Most oocytes extruded a second polar body and formed one pronucleus when treated with 7% ethanol alone [35/43 (81%)]. With ethanol followed by cytochalasin B or D, overall activation frequency was 70% (309/441), with activated oocytes containing two pronuclei. The cleavage rate was not significantly different between treatment with ethanol alone and ethanol followed by 5 micrograms mL-1 cytochalasin B, but it was significantly lower than in fertilized oocytes (P < 0.01). However, the blastocyst production rate was significantly different (P < 0.01) among the treatments. The incidence of parthenogenetic embryos with normal (diploid) complements and with chromosome anomalies (2N/4N) was 68% (17/25) and 32% (8/25) respectively, and this was not affected by cryopreservation treatment. The longitudinal diameter of aggregated-four embryos cultured in vitro was greater (P < 0.01) than aggregated-two or single embryos. One of the aggregated-four parthenogenetic embryos was further cultured in vitro and developed up to Day 27 after activation, with a diameter of 2980 microns. The aggregated-four parthenogenetic embryos were transferred to five recipients. The oestrus was prolonged in three recipients and they returned to oestrus on Day 57, 62 and 67 after the previous oestrus. These results indicate that aggregating parthenogenetic embryos can prolong their survival in vitro and in vivo.

Spontaneous Activation of the Hamster Egg in vivo

1973 ◽  
Vol 31 ◽  
pp. 548-549
Author(s):  
F. J. Longo
Keyword(s):  
Polar Body ◽  
Light And Electron Microscopy ◽  
Microscopic Level ◽  
Estrus Cycle ◽  
Light Microscopic Level ◽  
Cell Stage ◽  
Spontaneous Activation ◽  
Second Polar Body ◽  
Fertilized Egg

Spontaneous activation of the hamster ovum is a normal occurence in oviducal eggs that are not inseminated. Many aspects comprising this process of parthenogenesis mimic events characteristic of fertilization and include for example, the formation of the second polar body and the development of one or two pronuclei. Occasionally the activated egg cleaves to form a two-cell stage. The similarity between the spontaneously activated hamster ovum and the inseminated egg has been previously documented at the light microscopic level of investigation; however, further investigation is warranted for the study of parthenogenesis in mammals provides an opportunity of elucidating developmental mechanisms of the fertilized egg. Accordingly, unfertilized eggs were flushed from the oviducts of hamsters at different intervals during the estrus cycle (6 to 70 hours postovulation), prepared for light and electron microscopy, and compared with fertilized eggs obtained at corresponding periods.

scholarly journals Fiber-integrated Brillouin microspectroscopy: Towards Brillouin endoscopy

2017 ◽  
Vol 10 (06) ◽  
pp. 1742002 ◽  
Author(s):  
Irina V. Kabakova ◽  
YuChen Xiang ◽  
Carl Paterson ◽  
Peter Török
Keyword(s):  
Optical Fiber ◽  
Brillouin Scattering ◽  
Region Of Interest ◽  
The Body ◽  
Propagation Model ◽  
Micromechanical Characterization ◽  
First Time

Brillouin imaging (BI) for micromechanical characterization of tissues and biomaterials is a fast-developing field of research with a strong potential for medical diagnosis of disease-modified tissues and cells. Although the principles of BI imply its compatibility with in vivo and in situ measurements, the integration of BI with a flexible catheter, capable of reaching the region of interest within the body, is yet to be reported. Here, for the first time, we experimentally investigate integration of the Brillouin spectroscope with standard optical fiber components to achieve a Brillouin endoscope. The performance of single-fiber and dual-fiber endoscopes are demonstrated and analyzed. We show that a major challenge in construction of Brillouin endoscopes is the strong backward Brillouin scattering in the optical fiber and we present a dual-fiber geometry as a possible solution. Measurements of Brillouin spectra in test liquids (water, ethanol and glycerol) are demonstrated using the dual-fiber endoscope and its performance is analyzed numerically with the help of a beam propagation model.

scholarly journals Fyn kinase is involved in cleavage furrow ingression during meiosis and mitosis

Reproduction ◽  
2010 ◽  
Vol 140 (6) ◽  
pp. 827-834 ◽  
Author(s):  
Mattan Levi ◽  
Bernard Maro ◽  
Ruth Shalgi
Keyword(s):  
Cell Cycle Control ◽  
Polar Body ◽  
Mitotic Division ◽  
Dominant Negative ◽  
Confocal Imaging ◽  
Cleavage Furrow ◽  
Filamentous Actin ◽  
Fyn Kinase ◽  
Second Polar Body ◽  
First Time

Fertilization of mammalian oocytes triggers their exit from the second meiotic division metaphase arrest. The extrusion of the second polar body (PBII) that marks the completion of meiosis is followed by the first mitotic cleavage of the zygote. Several lines of evidence in somatic cells imply the involvement of Fyn, an Src family kinase (SFK), in cell cycle control and actin functions. In this study, we demonstrate, using live cell confocal imaging and microinjection of Fyn cRNAs, the recruitment of Fyn to the oocyte's cortical area overlying the chromosomes and its colocalization with filamentous actin (F-actin) during exit from the meiotic metaphase. Fyn concentrated asymmetrically at the cortical site designated for ingression of the PBII cleavage furrow, where F-actin had already been accumulated, and then redispersed throughout the entire cortex only to be recruited again to the cleavage furrow during the first mitotic division. Although microinjection of dominant negative Fyn did not affect initiation of the cleavage furrow, it prolonged the average duration of ingression, decreased the rates of PB extrusion and of the first cleavage, and led to the formation of bigger PBs and longer spindles. Extrusion of the PBII was blocked in oocytes exposed to SU6656, an SFK inhibitor. Our results demonstrate, for the first time, a continuous colocalization of Fyn and F-actin during meiosis and imply a role for the SFKs, in general, and for Fyn, in particular, in regulating pathways that involve actin cytoskeleton, during ingression of the meiotic and mitotic cleavage furrows.

scholarly journals Spatiotemporal characterization of periocular mesenchyme heterogeneity during anterior segment development

2019 ◽  
Author(s):  
Kristyn L. Van Der Meulen ◽  
Oliver Vöcking ◽  
Megan L. Weaver ◽  
Jakub K. Famulski
Keyword(s):  
Expression Patterns ◽  
Anterior Segment ◽  
Critical Event ◽  
Transgenic Zebrafish ◽  
Anterior Segment Dysgenesis ◽  
Heterogenous Population ◽  
First Time

ABSTRACTEstablishment of the ocular anterior segment (AS) is a critical event during development of the vertebrate visual system. Failure in this process leads to Anterior Segment Dysgenesis (ASD), which is characterized by congenital blindness and predisposition to glaucoma. The anterior segment is largely formed via a neural crest-derived population, the Periocular Mesenchyme (POM). In this study, we aimed to characterize POM behaviors and identities during zebrafish AS development. POM distributions and migratory dynamics were analyzed using transgenic zebrafish embryos (Tg[foxC1b:GFP], Tg[foxD3:GFP], Tg[pitx2:GFP], Tg[lmx1b.1:GFP], and Tg[sox10:GFP] throughout the course of early AS development (24-72hpf). In vivo imaging analysis revealed unique AS distribution and migratory behavior among the reporter lines, suggesting AS mesenchyme (ASM) is a heterogenous population. This was confirmed using double in situ hybridization. Furthermore, we generated ASM transcriptomic profiles from our reporter lines and using a four-way comparison analysis uncovered unique ASM subpopulation expression patterns. Taken together, our data reveal for the first time that AS-associated POM is not homogeneous but rather comprised of several unique subpopulations identifiable by their distributions, behaviors, and transcriptomic profiles.

scholarly journals Role of calcium ions in the control of embryogenesis of Xenopus. Changes in the subcellular distribution of calcium in early cleavage embryos after treatment with the ionophore A23187.

1979 ◽  
Vol 80 (3) ◽  
pp. 589-604 ◽  
Author(s):  
J C Osborn ◽  
C J Duncan ◽  
J L Smith
Keyword(s):  
Divalent Cations ◽  
Subsequent Development ◽  
Abnormal Development ◽  
Ionophore A23187 ◽  
Early Cleavage ◽  
Amphibian Embryo ◽  
High Incidence ◽  
Intracellular Action

Treatment of stage 5 Xenopus embryos with the ionophore A23187 for only 10 min, in the absence of extracellular Mg2+ and Ca2+, causes cortical contractions and a high incidence of abnormal embryos during subsequent development. Cation analysis shows that divalent ions are not lost from the embryos, but that Ca2+ is redistributed within the subcellular fractions. Ca2+ is probably released from yolk platelets and/or pigment granules by the action of A23187, [Ca2+] rises in the cytosol, and the mitochondria attempt to take up this free Ca2+. The mitochondria concomitantly undergo characteristic ultrastructural transformations, changing towards energized-twisted and energized-zigzag conformations. A23187 allows these changes to be demonstrated in situ. Extracellular divalent cations (10(-4) M) interfere with this intracellular action of A23187. Intracellular accumulation of Na+ (by treatment with ouabain) or Li+ also causes abnormal development, probably by promoting a release of Ca2+ from the mitochondria. It is suggested (a) that all these treatments cause a rise in [Ca2+]i which interferes with normal, integrated cell division, so causing, in turn, abnormal embryogenesis, (b) that levels of [Ca2+]i are of importance in regulating cleavage, (c) that the mitochondria could well have a function in regulating [Ca2+]i during embryogenesis in Xenopus, and (d) that vegetalizing agents may well act by promoting a rise in [Ca2+]i in specific cells in the amphibian embryo.

scholarly journals Morphology of gametes, post-fertilization events and the effect of temperature on the embryonic development of Astyanax altiparanae (Teleostei, Characidae)

Zygote ◽  
2016 ◽  
Vol 24 (6) ◽  
pp. 795-807 ◽  
Author(s):  
Matheus Pereira dos Santos ◽  
George Shigueki Yasui ◽  
Pedro Luiz Porfírio Xavier ◽  
Nadya Soares de Macedo Adamov ◽  
Nivaldo Ferreira do Nascimento ◽  
...  
Keyword(s):  
Developmental Stages ◽  
Polar Body ◽  
Effect Of Temperature ◽  
Male And Female ◽  
Fundamental Information ◽  
Spherical Head ◽  
Typical Morphology ◽  
Female Pronucleus ◽  
Second Polar Body ◽  
First Time

SummaryThe aim of this study was to describe the morphology of gametes, post-fertilization events and subsequent temperature effects on the early developmental stages of the neotropical species Astyanax altiparanae. The sperm of this species presents a typical morphology of teleost sperm with a spherical head (diameter = 1.88 µm), midpiece (diameter = 0.75 µm) and a single flagellum (length = 18.67 µm). The extrusion of the second polar body and fusion of male and female pronucleus were reported for the first time in this species. Additionally, we observed the formation of the fertilization cone, which prevents polyspermic fertilization. Developmental stages at 22°C, 26°C and 30°C gave rise to fertilization rates at 91.12, 91.42 and 93.04% respectively. Hatching occurred at 25 hpf at 22°C, 16 hpf at 26°C and 11 hpf at 30°C and the hatching rates were 61.78%, 62.90% and 59.45%, respectively. At 22°C, the second polar body was extruded at ≈6 mpf and the male and female pronucleus fused at ≈10 mpf. This fundamental information is important for the field and opens up new possibilities in fish biotechnology, including micromanipulation and chromosome-set manipulation.

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