Platelet activating factor (PAF) enhances mitosis in preimplantation mouse embryos

1993 ◽  
Vol 5 (3) ◽  
pp. 271 ◽  
Author(s):  
C Roberts ◽  
C O'Neill ◽  
L Wright
Keyword(s):  
Mitotic Index ◽  
Platelet Activating Factor ◽  
Treated Group ◽  
Blastocyst Stage ◽  
Mouse Embryos ◽  
Cell Stage ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Web 2086

Preimplantation mouse embryos were used to determine whether the reported significant increase in embryo metabolism and viability achieved through supplementation of the culture medium with the ether phospholipid 1-o-alkyl-2-acetyl-sn-glycero-3-phosphocoline (platelet activating factor, PAF) is attributable to an enhanced rate of mitosis. Blastocyst-stage embryos cultured in the presence of 0.186 to 18.6 microM exogenous PAF had a significantly (P < 0.01) higher mitotic index (the proportion of cells arrested in metaphase following incubation in colchicine) than those cultured without PAF. At the 8-cell stage, 29% more blastomeres were in metaphase in the PAF-treated group (P < 0.01) 8 h after the addition of colchicine, but by 16 h there was no difference between groups; thus, PAF increased the rate at which cells entered metaphase but did not increase the total number. The mitotic index showed a negative correlation with the number of cells within blastocysts. PAF had a significantly (P < 0.01) greater impact on the mitotic index of blastocysts with fewer cells. The action of PAF was specific, being completely blocked by the PAF-receptor antagonist WEB 2086 (33 microM). In the absence of exogenous PAF the mitotic index was lower with WEB 2086 than without, suggesting inhibition of the action of endogenous embryo-derived PAF. These results show that PAF stimulates the rates at which cells within the preimplantation mouse embryo enter metaphase in vitro and suggest that it would decrease their doubling time, perhaps accounting for the embryotrophic actions of PAF.

Normal adenylate ribonucleotide content in mouse embryos homozygous for the t12 mutation

Development ◽  
1983 ◽  
Vol 78 (1) ◽  
pp. 43-51
Author(s):  
Horst Spielmann ◽  
Robert P. Erickson
Keyword(s):  
In Vitro Culture ◽  
Normal Values ◽  
Firefly Luciferase ◽  
Blastocyst Stage ◽  
Mouse Embryos ◽  
Luciferase Assay ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse

The recently improved firefly luciferase assay was used to determine ATP, ADP or AMP in single preimplantation mouse embryos from crosses yielding lethal t12/t12 embryos. Normal values of the three adenylate ribonucleotides were found in freshly collected 2-cell and 4-cell embryos and during in vitro culture to the blastocyst stage. A decrease in adenylate ribonucleotide content was seen in putative t12/t12 embryos only when they were degenerating.

scholarly journals Changes in responsiveness of preimplantation mouse embryos to serum

Development ◽  
1978 ◽  
Vol 45 (1) ◽  
pp. 295-301
Author(s):  
Simon B. Fishel ◽  
M. Azim H. Surani
Keyword(s):  
Bovine Serum ◽  
Rna Synthesis ◽  
Blastocyst Stage ◽  
Mouse Embryos ◽  
The Other ◽  
Cell Stage ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Serum Albumen

Changes in uptake of radioactive uridine and its incorporation into RNA were determined in preimplantation mouse embryos, from the 2-cell to the blastocyst stage, as a measure of their responsiveness to extracellular conditions. Two media were tested, one contained serum and the other contained bovine serum albumen as a control. An increase in the acid-soluble pool occurred at the 8-cell stage and a marked increase in RNA synthesis occurred at the early blastocyst stage when the embryos were incubated with serum.

The effect of microtubule- and microfilament-disrupting drugs on preimplantation mouse embryos

Development ◽  
1980 ◽  
Vol 60 (1) ◽  
pp. 71-82
Author(s):  
G. Siracusa ◽  
D. G. Whittingham ◽  
M. De Felici
Keyword(s):  
Blastocyst Stage ◽  
Mouse Embryos ◽  
Microtubule Assembly ◽  
Continuous Exposure ◽  
Blastocyst Formation ◽  
Multipolar Spindles ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Continuous Presence

The sensitivity of early preimplantation mouse embryos to drugs which disrupt microfilament function (cytochalasin B-CB and cytochalasin D-CD) and microtubule assembly (colchicine, colcemid, vinblastine and griseofulvin) was examined. CD inhibited cleavage at a concentration 35-fold lower than CB (3 × 10−7 M ν. 1 × 10−5 M). Treatment of 2-cell embryos for 6 h with 1 × 10−5 M CB or 1 × 10−6 M CD or continuous exposure to lower concentrations of CB or CD did not affect development to the blastocyst stage in vitro. Vinblastine inhibited cleavage at a concentration tenfold lower than colcemid or colchicine (1 × 10−8 M ν. 1 × 10−7 M). The continuous presence of colcemid at 10−8 M did not affect the development of 2-cell embryos to the blastocyst stage, but development was reduced with vinblastine at 1 × 10−8 M and completely inhibited with colchicine at 1 × 10−8 M. The drugs produced similar responses when 2-cell embryos were treated for 6 h with concentrations that inhibited cleavage. Complete inhibition of cleavage was obtained after only a 2 h exposure to 2 × 10−7 M colchicine. A similar concentration of lumicolchicine did not affect cleavage or blastocyst formation. Embryos were less sensitive to griseofulvin; the first cleavage division was unaffected by concentrations as high as 3 × 10−4 M and only 50% of 2-cell embryos failed to cleave in 1 × 10 1 and 3 × 10−4 M griseofulvin. At these concentrations a small proportion of 1-cell embryos and the majority of the 2-cell embryos showed unequal cytoplasmic division probably caused by the formation of multipolar spindles. The continuous exposure of 2-cell embryos to 3 × 10−5 M griseofulvin did not affect blastocyst formation.

Cyclic AMP reversal of hypoxanthine-arrested preimplantation mouse embryos is EDTA-dependent

Zygote ◽  
1996 ◽  
Vol 4 (2) ◽  
pp. 129-137 ◽  
Author(s):  
Mary K. Dienhart ◽  
Stephen M. Downs
Keyword(s):  
Embryo Development ◽  
Culture Media ◽  
Phosphodiesterase Inhibitor ◽  
Blastocyst Stage ◽  
Mouse Embryos ◽  
Cooperative Interaction ◽  
Basic Salt ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse

SummaryHypoxanthine can block preimplantation mouse embryo development in vitro at the 2- to 4-cell stages, and this has recently been shown to be reversed by cAMP-elevating agents. However, the extent of this hypoxanthine-induced arrest is determined by the culture conditions and strain of mouse. Whitten's and KSOM/AA are two embryo culture media that support preimplantation development to the blastocyst stage. This study was undertaken to examine the influence of several components in these media on hypoxanthine-arrested preimplantation mouse embryos and to test the hypothesis that reversal of the hypoxanthine block by cAMP-elevating agents requires cooperative interaction with the chelator, EDTA. Initial experiments demonstrated that embryo development was blocked in the presence of hypoxanthine in Whitten's medium but not in KSOM/AA; furthermore, removal of EDTA from KSOM/AA rendered this medium incapable of supporting high levels of development to blastocyst (9%), whereas high numbers of blastocysts (80%) formed in Whitten's medium, which does not contain the chelator. Consequently, Whitten's medium was used to test our hypothesis. It has previously been demonstrated that the phosphodiesterase inhibitor, IBMX, can reverse the developmental arrest imposed by hypoxanthine in EDTA-supplemented Earle's basic salt solution, but in the present study the addition of IBMX to Whitten's medium resulted in a block to development and failed to reverse the hypoxanthine arrest. These disparate effects can be explained by the presence or absence of EDTA. Supplementing Whitten's medium with EDTA reverses the IBMX effect, but not the hypoxanthine-induced block. While IBMX alone is unable to reverse the hypoxanthine block in Whitten's medium, development is greatly enhanced by the simultaneous addition of EDTA and IBMX. Similar results were obtained with the cAMP analogue, 8-AHA-cAMP. The data therefore support our hypothesis that the reversal of the hypoxanthine-induced arrest by cAMP-elevating agents is critically dependent on the presence of EDTA. We contrast this with the situation in mouse oocytes, where the hypoxanthine-induced meiotic arrest is not reversed by the addition of EDTA and/or cAMP-elevating agents.

Identification of a 2-cell stage specific inhibitor of the cleavage of preimplantation mouse embryos synthesized by rat hepatoma cells as 5′-deoxy-5′-methylthioadenosine

Zygote ◽  
2010 ◽  
Vol 19 (2) ◽  
pp. 117-125 ◽  
Author(s):  
Masayuki Kobayashi ◽  
Koichi Saito ◽  
Shigeru Tamogami ◽  
Junko Takashima ◽  
Kano Kasuga ◽  
...  
Keyword(s):  
Biological Activities ◽  
Specific Inhibitor ◽  
Biological Properties ◽  
Mouse Embryos ◽  
Cell Stage ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Mammalian Embryos ◽  
Rat Hepatoma

SummaryRat hepatoma Reuber H-35 cells produce a unique compound designated as Fr.B-25, a 2-cell stage-specific inhibitor of the cleavage of preimplantation mouse embryos cultured in vitro. Here, we identified Fr.B-25 as a purine nucleoside, 5′-deoxy-5′-methylthioadenosine (MTA), by mass spectroscopic analysis. All of the biological activities examined of authentic MTA on the development of mouse zygotes were indistinguishable from those of Fr.B-25. The mechanism of MTA action in the development of preimplantation mouse embryos was probably different from those of hypoxanthine and adenosine, which are well-characterized purine nucleosides that act as inhibitors of the cleavage of mouse 2-cell embryos. From the shared molecular and biological properties of Fr.B-25 and MTA, we concluded that Fr.B-25 is MTA. To the best of our knowledge, this is the first delineation of the effect of MTA on the development of preimplantation mammalian embryos cultured in vitro.

The effect of 5-bromodeoxyuridine on cell division and differentiation of preimplantation mouse embryos

Development ◽  
1976 ◽  
Vol 35 (1) ◽  
pp. 169-178
Author(s):  
D. R. Pollard ◽  
M. M. Baran ◽  
R. B. Bachvarova
Keyword(s):  
Cell Division ◽  
Cell Number ◽  
Mouse Embryos ◽  
Cell Stage ◽  
Average Cell ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Excess Thymidine ◽  
System Cell

Mouse embryos exposed to concentrations of 5-bromodeoxyuridine (BUdR) ranging from 0·01 to 1·0 μg/ml in vitro for two days from the 8-cell stage exhibit a concentration-dependent decrease in the frequency of normal blastocysts and a decrease in average cell number per embryo. A 20-h exposure was adequate to achieve the full BUdR response. Both effects were eliminated in the presence of excess thymidine. Autoradiographs demonstrated that BUdR[3H] was incorporated into DNA during the first and second day of culture. Thus, BUdR appears to act through incorporation into DNA; and, in this system, cell division is at least as sensitive to BUdR as is differentiation.

Human Adenovirus Uptake by Preirnplantation Mouse Embryos

1972 ◽  
Vol 30 ◽  
pp. 268-269
Author(s):  
D. G. Chase ◽  
W. Winters ◽  
L. Piko
Keyword(s):  
Hela Cells ◽  
Human Adenovirus ◽  
Mouse Embryos ◽  
Equilibrium Density ◽  
Cell Stage ◽  
Virus Attachment ◽  
Preimplantation Mouse Embryos ◽  
Embryo Culture Medium ◽  
Preimplantation Mouse ◽  
Mouse Cells

Although the outlines of human adenovirus entry and uncoating in HeLa cells has been clarified in recent electron microscope studies, several details remain unclear or controversial. Furthermore, morphological features of early interactions of human adenovirus with non-permissive mouse cells have not been extensively documented. In the course of studies on the effects of human adenoviruses type 5 (AD-5) and type 12 on cultured preimplantation mouse embryos we have examined virus attachment, entry and uncoating. Here we present the ultrastructural findings for AD-5.AD-5 was grown in HeLa cells and purified by successive velocity gradient and equilibrium density gradient centrifugations in CsCl. After dialysis against PBS, virus was sedimented and resuspended in embryo culture medium. Embryos were placed in culture at the 2-cell stage in Brinster's medium.

Modification of cell division by phorbol ester in preimplantation mouse embryos

Development ◽  
1987 ◽  
Vol 101 (2) ◽  
pp. 403-408
Author(s):  
E.T. Mystkowska ◽  
W. Sawicki
Keyword(s):  
Cell Division ◽  
Video Recording ◽  
Mouse Embryos ◽  
Time Intervals ◽  
Cell Divisions ◽  
Stage Of Development ◽  
Preimplantation Mouse Embryos ◽  
Preimplantation Mouse ◽  
Single Blastomeres

2-cell mouse embryos were treated in vitro with a 2 h pulse of phorbol myristate acetate (PMA) at 32nd, 38th and 50th h after hCG, then chased in culture for up to 46 h. Embryos were fixed at various time intervals of chasing, then stained and inspected. Some embryos were carefully inspected with a video recording system, every 1.44s and the cell divisions (cytokinesis) as well as formation of large, single blastomeres, each from two smaller ones, were recorded. PMA pulse let to the suppression of cell divisions. The rate of the suppression was time dependent: with a delay of 0–1, 12 and 18 h between the PMA pulse and time of scheduled cell division about 99, 87 and 44% of 2-cell embryos remained at this stage of development, for at least 10 h, respectively, and 90, 58 and 12% of their blastomeres revealed binuclearity. Since we found that PMA-mediated formation of binuclearity was not the effect of cell fusions, it was assumed that the inhibition of cytokinesis preceded by karyokinesis was responsible for binuclearity. PMA effect on cell divisions was reversible. PMA-treated embryos revealed formation of large, single blastomeres, each from two smaller ones. If cell division appeared after PMA pulse, in about 52% of 3- to 6-cell embryos, the large blastomere formation was recorded in the course of the subsequent 38 h. Large blastomere formation was concluded to be the result of either cell fusion or reversion of incompleted cytokinesis brought about by PMA.

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