acrosomal reaction


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Acrosomal Reaction

A necessary and irreversible step in fertilisation, which is triggered by a sperm receptor, in which the sperm’s and ovum’s plasma membranes fuse and the sperm penetrates the ovum’s zona pellucida.

acrosomal reaction

Reproductive medicine A necessary and irreversible step in fertilization which is triggered by sperm receptor, in which the sperm's and ovum's plasma membranes fuse and the sperm penetrates the zona pellucida. Cf Capacitation.

acrosomal reaction

(ak″rŏ-sō′măl)
The release of enzymes from the acrosome on the head of the sperm. This process causes the sperm to penetrate the zona pellucida of the egg and begin fertilization.
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Pattern C: sperm cells displaying fluorescence on the head that was greater in intensity at the acrosomal zone, thus they were considered as undergoing acrosomal reaction. Table IV shows the percentage of intact sperm cells in fresh treatment and in those incubated with PVL.
Effects of progesterone, CatSper and Hv1 channel inhibitors on sperm acrosomal reaction Acrosome reacted sperm (%) Subgroups (n-24) Control Progesterone (1 [micro]M) Ham's F10 7.1[+ or -]0.8 21.9[+ or -]1.7 p<0.001 (*) NNC (2 [micro]M) 7.1[+ or -]0.8 7.7[+ or -]0.8 p<0.001 (*) Zn (1 mM) 8.9[+ or -]0.7 9.8[+ or -]4.7 p<0.001 (*) NNC + Zn 8.4[+ or -]0.7 7[+ or -]0.
* Combination of Trolox and EDTA partly improved frozen-thawed sperm motility and reduced the spontaneous acrosomal reaction of sperm.
This might reflect an increase of acrosomal volume, which could be related to the acrosomal reaction process.
Cholesterol and zinc usually stabilize sperm cell membrane and must be removed during capacitation to enable acrosomal reaction and penetration of the ova.
In one study, the induction of the acrosomal reactions using ionophore A23587 from 17.4 to 36.1% significantly increased the percentage of vacuole-free spermatozoa from 41.2% to 63.8% (P < 0.001) [21].
Intracellular calcium regulation in sperm capacitation and acrosomal reaction. Mol.
Taurine prevents efflux of cholesterol from the sperm membrane and MDA production in diluents which indicates it prevents premature capacitation and acrosomal reaction that act as an antioxidant.
Then spermatozoa adhere to the oocytes zona pellucida to induce the acrosomal reaction, in which the fusion of the spermatozoal plasma membrane and the outer acrosomal membrane occurs to allow the acrosomal enzymes to be released.
At this point you might be wondering how binding of the sperm to the zona pellucida induces the morphologic changes associated with the acrosomal reaction. The best way to understand this process is to view the interaction between the egg-binding protein and ZP3 as analogous to the interaction between a receptor and its hormone.
Induction of the acrosomal reaction in mouse spermatozoa by the solution of pellucid zone from alpaca (Lama pacos L.)
The second, third and fourth steps of this process, respectively, are the acrosomal reaction, the sperm cell and egg cell adhesion through the vitelline envelope, and the actual membrane contact between the two cells.