Effects of extremely low osmolarity on fertilized mouse eggs

Development ◽  
1977 ◽  
Vol 37 (1) ◽  
pp. 65-77
Author(s):  
Jolanta Opas
Keyword(s):  
Water Treatment ◽  
Zona Pellucida ◽  
Polar Body ◽  
Preimplantation Development ◽  
Distilled Water ◽  
Second Polar Body ◽  
Mouse Eggs

When fertilized one-cell eggs are subjected to distilled water treatment for 2–6 min, cytoplasm bulges through the sperm-slit in the zona pellucida and forms a cytoplasmic fragment (CF). CFs were observed in 86·5 % of eggs; in 20·9 % of cases CFs contained a pronucleus (or pronuclei). In 53·4 % of eggs permanent incorporation of the second polar body (2 P.B.) into the egg cytoplasm occurred. These phenomena occurring in different combinations produced 6·2 % of haploid eggs, 10·3 % of diploid eggs with a pronucleus replaced by 2 P.B. nucleus, and 43·1 % of triploid eggs. 4·4 % t of eggs were enucleated. The remaining group comprised diploid eggs which were either not affected by the treatment (6·4 %) or lost a certain amount of cytoplasm by formation of an anucleate CF (29·6%). The frequencies of the types of reaction were related to the post-fertilization stage of eggs. All eggs except the enucleated ones were able to develop to the stage of morula or blastocyst. Triploids developed until the 12th day of pregnancy and diploids that had lost up to 15 % of the cytoplasm developed to term. There was a twofold reduction in the percentage of preimplantation development when treated eggs originated from induced rather than spontaneous ovulation.

scholarly journals Roles of heterotrimeric and monomeric G proteins in sperm-induced activation of mouse eggs

Development ◽  
1994 ◽  
Vol 120 (11) ◽  
pp. 3313-3323 ◽  
Author(s):  
G.D. Moore ◽  
T. Ayabe ◽  
P.E. Visconti ◽  
R.M. Schultz ◽  
G.S. Kopf
Keyword(s):  
G Protein ◽  
G Proteins ◽  
Zona Pellucida ◽  
Polar Body ◽  
Active Form ◽  
Dominant Negative ◽  
Egg Activation ◽  
Cell Stage ◽  
Second Polar Body ◽  
Mouse Eggs

Results of several lines of experimentation suggest that sperm-induced egg activation has several features in common with G protein-coupled receptor signal transduction mechanisms. We report that microinjection of GDP beta S into metaphase II-arrested mouse eggs blocks sperm-induced egg activation. Since GDP beta S inactivates both heterotrimeric and monomeric classes of G proteins, the involvement of members of each of these families in sperm-induced egg activation was evaluated. Neither pertussis toxin treatment of eggs nor microinjection of eggs with inhibitory antibodies toward G alpha q blocked sperm-induced egg activation. Nevertheless, microinjection of phosducin, a protein that binds tightly to free G protein beta gamma subunits, specifically inhibited second polar body emission, the fertilization evoked decrease of H1 kinase activity and pronucleus formation. Microinjection of phosducin, however, did not inhibit the fertilization-induced modifications of the zona pellucida and microinjection of beta gamma t did not result in egg activation in the absence of sperm. Inactivation of the monomeric Rho family of G proteins with C3 transferase from Clostridium botulinum inhibited emission of the second polar body and cleavage to the 2-cell stage, but did not affect the modifications of the zona pellucida or pronucleus formation. Microinjection of Rasval12, which is a constitutively active form of Ras, did not result in egg activation in the absence of sperm. Moreover, microinjection of either an anti-Ras neutralizing antibody (Y13-259) or a dominant negative form of Ras (RasT) did not affect events of sperm-induced egg activation. In contrast, microinjection of RasT inhibited embryo cleavage to the 2-cell stage. These results suggest that both heterotrimeric and monomeric G proteins are involved in various aspects of sperm-induced egg activation.

Fertilisation in the Rabbit

1932 ◽  
Vol 9 (4) ◽  
pp. 403-408
Author(s):  
G. PINCUS ◽  
E. V. ENZMANN
Keyword(s):  
Zona Pellucida ◽  
Critical Period ◽  
Polar Body ◽  
Follicle Cells ◽  
Fallopian Tubes ◽  
Sperm Penetration ◽  
Pass Through ◽  
Second Polar Body

The series of events occurring in the Fallopian tubes of rabbit does mated to fertile bucks may be summarised as follows: The ova liberated from the ovaries and surrounded by the follicle cells become massed together. Sperm penetrate the massed follicle cells, which fall away as the sperm pass through them. At from 1½-3 hours after ovulation the spermatozoa reach the egg. A number of spermatozoa pass through the zona pellucida, but only one, apparently, enters the egg. At the time of sperm penetration the egg shrinks slightly but definitely. The second polar body is given off 45 min. or longer after sperm penetration. The pronuclei are formed after the formation of the second polar body and, at the earliest, 3 hours after ovulation. The critical period for sperm penetration appears to occur at 2-3 hours after ovulation (cf. Pincus,1930).

Timing of the First Cleavage Division of Haploid Mouse Eggs, and the Duration of its Component Stages

1973 ◽  
Vol 13 (2) ◽  
pp. 553-566 ◽  
Author(s):  
M. H. KAUFMAN
Keyword(s):  
Polar Body ◽  
Time Lapse ◽  
Follicle Cells ◽  
Cleavage Division ◽  
Cell Stage ◽  
Cell Embryo ◽  
Second Polar Body ◽  
Polar Body Extrusion ◽  
Mouse Eggs

Mouse eggs were activated by treatment with hyaluronidase which removed the follicle cells, followed by culture in vitro, and examined at the first cleavage mitosis. Second polar body extrusion usually occurred and haploid parthenogenesis was initiated. Air-dried chromosome preparations were made between 11 and 15.5 h after activation. Out of the 308 eggs examined 74 had already progressed to the 2-cell stage; the remaining 234 at the 1-cell stage were examined in detail. All chromosome preparations of the first cleavage mitosis were classified into groups corresponding with the stages of prometaphase, metaphase (early or ‘pre-chromatid’, ‘chromatid’ and ‘late chromatid’) and anaphase. An indirect estimate was made of the duration of the first cleavage mitosis and of its component stages from the incidence of stages observed at different time intervals after activation. Similar eggs were also observed at 37 °C by time-lapse cine-photography and the interval between the disappearance of the pronucleus to the beginning of telophase of the first cleavage division was determined. The results of timing studies on the haploid eggs were compared with results obtained from similar observations on the first cleavage division of fertilized eggs which would of course normally be diploid. Artificially activated eggs with 2 pronuclei, resulting from second polar body suppression, were also examined, and serial chromosome preparations during mitosis showed that the 2 pronuclear chromosome groups unite on the first cleavage spindle and divide to give a hetero-zygous diploid 2-cell embryo.

In vitro activation of mouse eggs

Development ◽  
1974 ◽  
Vol 31 (2) ◽  
pp. 497-512
Author(s):  
C. F. Graham ◽  
Z. A. Deussen
Keyword(s):  
Dna Synthesis ◽  
Culture Medium ◽  
Tritiated Thymidine ◽  
Polar Body ◽  
Similar Time ◽  
Body Formation ◽  
Polar Body Formation ◽  
Second Polar Body ◽  
Mouse Eggs

Unfertilized mouse eggs were activated in vitro with hyaluronidase. Subsequently they were exposed to culture medium at different osmolarities. In full strength White's culture medium they tended to form one pronucleus and a second polar body. The majority of these eggs were haploid. In 4/5 and 3/5 dilutions of this medium, the second polar body formation was suppressed and eggs tended to form with one or two pronuclei. Those with one pronucleus were diploid and those with two pronuclei could either form a diploid or form a haploid mosaic. Old eggs tended to immediately cleave and form haploid mosaics. DNA synthesis was studied in activated eggs using tritiated thymidine and autoradiography. DNA synthesis occurred at a similar time in fertilized and activated eggs.

The chromosome complement of single-pronuclear haploid mouse embryos following activation by ethanol treatment

Development ◽  
1982 ◽  
Vol 71 (1) ◽  
pp. 139-154
Author(s):  
M. H. Kaufman
Keyword(s):  
Polar Body ◽  
Chromosome Complement ◽  
Control Groups ◽  
High Incidence ◽  
Aneuploid Chromosome ◽  
Pre Treatment ◽  
Second Polar Body ◽  
Polar Body Extrusion ◽  
Mouse Eggs ◽  
Very High

A technique in which mouse eggs are stimulated to develop parthenogenetically following their brief incubation in 7% ethanol in PBS is described. Very high rates of activation were achieved, and a detailed analysis presented of the class of parthenogenone which develops a single haploid pronucleus following second polar body extrusion. As preliminary studies on presumptive haploid morulae indicated that a proportion of the metaphase spreads examined had an aneuploid chromosome constitution, the incidence of aneuploidy at the first cleavage mitosis was investigated. In the control groups the level of aneuploidy was about 1%, whereas in the ethanol-treated series the incidence ranged from 13·6–18·8%. Additional pre-treatment of ethanol-activated oocytes in low osmolar medium raised the incidence of aneuploidy to 28·3%. Metaphase groups with 18, 19, 21 and 22 chromosomes present were observed in addition to groups with a normal complement of 20 chromosomes. The possible mode of action of ethanol in inducing parthenogenetic activation of mouse oocytes, and a high incidence of aneuploidy, is discussed in relation to previous knowledge of the action of this agent. Preliminary studies using G-banding indicate that the aneuploidy observed appears to arise as a result of non-disjunction which may involve any of the chromosomes of the complement.

Induction of triploidy in the mouse by cytochalasin B

Development ◽  
1975 ◽  
Vol 34 (2) ◽  
pp. 279-289
Author(s):  
Anna Niemierko
Keyword(s):  
Culture Medium ◽  
Cytochalasin B ◽  
Sex Chromosome ◽  
Polar Body ◽  
Cell Number ◽  
Second Polar Body ◽  
And Control ◽  
Mouse Eggs

Mouse eggs fertilized in vivo were treated with cytochalasin B in vitro (5 μg/ml of culture medium) at he moment of extrusion of the second polar body (2·5, 3·0, 3·5 h after copulation). Cytochalasin B inhibits cytokinesis of the second maturation division, so that triploid digynic eggs are formed in over 50% of treated eggs. Triploid eggs were transplanted to the oviducts of recipients. On the 4th and 5th day of development 41·7% of transplanted eggs were recovered. All embryos recovered on the 4th day were morulae, while on the 5th day blastocysts predominated. Recovered embryos were studied for cell number and ploidy. Twenty-three of 27 embryos with analysable metaphase plates were triploid and four were diploid (the latter were found in females into which both triploid and control diploid eggs were transplanted). Sex chromosome constitution was determined in seven cases: four triploids were XXY and three were XXX.

scholarly journals Bushen Tiaojing (II and III) Decoctions Activate MAPK14 and MAPK3/1 to Promote the Expression of Cumulus Expansion-Related Factors in Mice

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Xiao Liang ◽  
Xue Tong ◽  
Hui-lan Du ◽  
Ming He ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Western Blot ◽  
Polar Body ◽  
Cumulus Cell ◽  
Serum Levels ◽  
Control Group ◽  
Distilled Water ◽  
Related Factors ◽  
Cumulus Expansion ◽  
Sequential Administration ◽  
First Polar Body

Background. Bushen Tiaojing Decoctions (BSTJ-II-D and BSTJ-III-D) are used to assist pregnancy in clinical practice. In this study, we explored the ability of sequential administration of BSTJ-II-D and BSTJ-III-D to promote cumulus cell (CC) expansion and its underlying mechanisms in controlled ovarian hyperstimulation (COH) mice. Methods. Kunming mice were randomly divided into three groups. The normal group was injected intraperitoneally with saline, and distilled water was administered orally by gavage. As the COH model, mice were injected with GnRHa, eCG, and hCG. Subsequently, the BSTJD group received BSTJ-II-D and BSTJ-III-D orally by gavage, while the control group received distilled water. We evaluated CC expansion and oocyte first polar body (PB1) extrusion under a stereomicroscope. Serum levels of follicle-stimulating hormone (FSH) were detected by radioimmunoassay. The expression of the CC expansion-related factors PTX3 and PTGS2 was detected by immunofluorescence, western blot, and quantitative real-time-polymerase chain reaction analyses (qRT-PCR). Expression of p-MAPK14, p-MAPK3/1, MAPK14, and MAPK3/1 was detected by western blot analysis. Results. Sequential administration of BSTJ-II-D and BSTJ-III-D promoted cumulus expansion and oocyte PB1 extrusion and upregulated PTX3 and PTGS2 expression at the mRNA and protein levels. Furthermore, the levels of p-MAPK14/MAPK14, p-MAPK3/1/MAPK3/1 proteins, and serum FSH in the BSTJD group were higher than those in the normal and control groups. Conclusions. Sequential administration of BSTJ-II-D and BSTJ-III-D promotes cumulus expansion and oocyte maturation in COH mice by increasing FSH expression and activating the MAPK14 and MAPK3/1 signalling pathways, thereby increasing expression of PTX3 and PTGS2.

scholarly journals P57 A new technique for polar body biopsy with laser tweezers and femtosecond laser zona pellucida drilling

2010 ◽  
Vol 20 ◽  
pp. S41-S42
Author(s):  
S.A. Sergeev ◽  
M.M. Rakityanskiy ◽  
Y.V. Khramova ◽  
M.L. Semenova ◽  
A.A. Smirnova ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Zona Pellucida ◽  
Polar Body ◽  
New Technique ◽  
Laser Tweezers ◽  
Polar Body Biopsy ◽  
A New Technique
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