Effect of Enucleation on Inactivation of Cytostatic Factor Activity in Matured Rat Oocytes

2007 ◽  
Vol 9 (2) ◽  
pp. 257-266 ◽  
Author(s):  
Junya Ito ◽  
Megumi Kato ◽  
Shinichi Hochi ◽  
Masumi Hirabayashi
Keyword(s):  
Factor Activity ◽  
Cytostatic Factor

Progression of mouse oocytes from metaphase I to metaphase II is inhibited by fusion with G2 cells

Zygote ◽  
2000 ◽  
Vol 8 (2) ◽  
pp. 145-151 ◽  
Author(s):  
Joanna Grabarek ◽  
Magdalena Zernicka-Goetz
Keyword(s):  
Chromosome Condensation ◽  
Factor Activity ◽  
Premature Chromosome Condensation ◽  
Mouse Oocytes ◽  
M Phase ◽  
G2 Cells ◽  
Cytostatic Factor ◽  
Metaphase Ii Oocytes ◽  
Metaphase I

We show that in contrast to metaphase II oocytes, metaphase I oocytes cannot be activated by fusion with the zygote. Fusion of metaphase I oocytes with G2 zygotes was followed by premature chromosome condensation, with 60% of the hybrids becoming arrested at metaphase I, the remainder progressing and arresting at metaphase II. Hybrids of metaphase I oocytes and M-phase zygotes underwent accelerated maturation, but all arrested at metaphase II. In both cases the arrest could be overcome by treatment with the parthenogenetic activators ethanol and cycloheximide. We discuss these findings in relation to the possibility that the metaphase I oocyte contains cytostatic factor activity that is activated by its zygotic partner. Alternatively, the G2 zygote may provide an inhibitor of anaphase, normally never present in the metaphase I oocyte and which is absent from the M-phase zygote.

Consumption of Hageman Factor Activity in the Generalized Shwartzman Reaction Induced by Liquoid

1970 ◽  
Vol 23 (02) ◽  
pp. 386-404 ◽  
Author(s):  
G Müller-Berghaus ◽  
H. G Lasch
Keyword(s):  
Partial Thromboplastin Time ◽  
Lethal Dose ◽  
Control Group ◽  
Factor V ◽  
Consumption Coagulopathy ◽  
Factor Activity ◽  
Hageman Factor ◽  
Intravascular Coagulation ◽  
Shwartzman Reaction

SummaryThe role of Hageman factor in triggering intravascular coagulation has been studied in rabbits injected intravenously with Liquoid. Besides changes of coagulation parameters characteristic of consumption coagulopathy (e.g. decrease in platelet counts, fibrinogen levels, factor V activity), a pronounced drop in Hageman factor activity was observed after injection of Liquoid. Likewise, the partial thromboplastin time became prolonged.The activation of Hageman factor in vivo could be prevented by intravenous infusion of lysozyme. Twenty min after starting the lysozyme infusion, the partial thromboplastin time became prolonged from a mean of 29 sec to 108 sec. Animals infused with lysozyme and injected with a lethal dose of Liquoid did not develop a consumption coagulopathy. In the same manner, none of 10 animals treated with lysozyme developed the generalized Shwartzman reaction, whereas in the control group 19 out of 20 animals showed fibrin thrombi in the glomerular capillaries.From the present study it may be concluded that the intravascular coagulation process after intravenous injection of Liquoid is triggered by Hageman factor activation.

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