Phospholipase C-ζ-induced Ca2+ oscillations cause coincident cytoplasmic movements in human oocytes that failed to fertilize after intracytoplasmic sperm injection.
OBJECTIVE
To evaluate the imaging of cytoplasmic movements in human oocytes as a potential method to monitor the pattern of Ca(2+) oscillations during activation.


METHODS
Test of a laboratory technique.


METHODS
University medical school research laboratory.


METHODS
Donated unfertilized human oocytes from intracytoplasmic sperm injection (ICSI) cycles.


METHODS
Microinjection of oocytes with phospholipase C (PLC) zeta (ζ) cRNA and a Ca(2+)-sensitive fluorescent dye.


METHODS
Simultaneous detection of oocyte cytoplasmic movements using particle image velocimetry (PIV) and of Ca(2+) oscillations using a Ca(2+)-sensitive fluorescent dye.


RESULTS
Microinjection of PLCζ cRNA into human oocytes that had failed to fertilize after ICSI resulted in the appearance of prolonged Ca(2+) oscillations. Each transient Ca(2+) concentration change was accompanied by a small coordinated movement of the cytoplasm that could be detected using PIV analysis.


CONCLUSIONS
The occurrence and frequency of cytoplasmic Ca(2+) oscillations, a critical parameter in activating human zygotes, can be monitored by PIV analysis of cytoplasmic movements. This simple method provides a novel, noninvasive approach to determine in real time the occurrence and frequency of Ca(2+) oscillations in human zygotes.
School of Medicine, Cardiff University, Heath Park, Cardiff, United Kingdom. Swannk1@cardiff.ac.uk
Karl
K
Swann
Shane
S
Windsor
Karen
K
Campbell
Khalil
K
Elgmati
Michail
M
Nomikos
Magdalena
M
Zernicka-Goetz
Nazar
N
Amso
F Anthony
FA
Lai
Adrian
A
Thomas
Christopher
C
Graham
D020013:Calcium Signaling; D003593:Cytoplasm / Q000201:enzymology*; D005260:Female; D005456:Fluorescent Dyes / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008845:Microinjections; D008856:Microscopy, Fluorescence; D009038:Motion; D009865:Oocytes / Q000201:enzymology*; D054801:Phosphoinositide Phospholipase C / Q000235:genetics / Q000378:metabolism*; D018075:RNA, Complementary / Q000008:administration & dosage; D012212:Rheology; D020554:Sperm Injections, Intracytoplasmic; D013997:Time Factors; D017211:Treatment Failure
D005456:Fluorescent Dyes; D018075:RNA, Complementary; C499235:PLCZ1 protein, human; D054801:Phosphoinositide Phospholipase C