@entity19 oocytes were treated with 8% @entity1068 for 3-6 min. The rate and pathways of parthenogenetic activation, occurrence of cortical reaction, and zona solubility changes were assessed in @entity167 -treated eggs. The incidence of parthenogenetic activation was greatest (91%) after 3-4-min exposure, and it was reduced (84%) after 5-6-min exposure to @entity167 . Also, the rate of haploid single pronucleate parthenogenones decreased and the rate of fragmented ova increased with increase time of exposure to @entity1068 . Ultrastructural observations showed occurrence of cortical reaction, disappearance and subsequent reappearance of short microvilli. A slight damage occurred to the ER in @entity167 -exposed ova. The zona dissolution assay utilizing alpha-chymotrypsin demonstrated decreased solubility of the zonae pellucidae after exposure to @entity167 . The zona dissolution t50 increased from 0.5-2.5 min in nontreated unfertilized oocytes to about 4 h in activated ova. The t50 of in vivo fertilized eggs was 4 1/2 h. Empty zonae exposed to @entity167 lysed at the same rate as nontreated control zonae did. The results indicate that activation of @entity19 oocytes with @entity167 initiates completion of meiosis and triggers the cortical reaction, which results in subsequent hardening of the zona pellucida.

Cortical reaction and zona hardening in XXXX oocytes following exposure to @entity1068 .

@entity19 :: ('10090', 'Species') :: ['Mouse', 'mouse'] @entity167 :: ('CHEBI:16236', 'Chemical') :: ['alcohol'] @entity1068 :: ('MESH:D000431', 'Chemical') :: ['ethanol']
@entity19 :: (10090,Species) :: ['mouse']
