Time-Lapse Dynamics of the Mouse Oocyte Chromatin Organisation during Meiotic Resumption

Table 1

Timing of events occurring during meiosis resumption of antral oocytes cultured in vitro.

Type of event	Mean ± S.D. in minutes	NSN oocytes	𝑃 value*
	SN oocytes
GVBD	34.2±8.1	51.4±19.0	<0.05
Increase of the perivitelline space	24.0±10.6	96.0±24.0	<0.001
Formation of 4-5 CHCs	92.4±9.9	ND**	—
Formation of 8–10 small pericentromeric regions (rosette)	223.2±20.8	139.2±20.9	<0.01
MI plate	350.2±34.6	390.7±20.5	<0.05
Anaphase I	483.6±33.0^∗∗∗	ND	—
Extrusion of polar body I and formation of MII plate	520.7±20.7^∗∗∗	ND	—

∗Comparison of SN versus NSN.
**Not detected.
***Calculated on 55% of oocytes that reached anaphase I within the 9 hr recording period.