Subscribe to thousands of academic journals for just $40/month
Read and share the articles you need for your research, all in one place.

Comparison of Ca2+ and CaMKII responses in IVF and ICSI in the mouse

Molecular Human Reproduction , Volume 13 (4): 265 – Apr 1, 2007


Oxford University Press
Copyright © 2010 European Society of Human Reproduction and Embryology
Publisher site
See Article on Publisher Site

Preview Only

Expand Tray Hide Tray

Comparison of Ca2+ and CaMKII responses in IVF and ICSI in the mouse


Abstract Novel methods of egg activation in human assisted reproductive technologies and animal somatic cell nuclear transfer are likely to alter the signalling process that occurs during normal fertilization. Intracytoplasmic sperm injection (ICSI) bypasses the normal processes of the acrosome reaction, sperm–egg fusion, and processing of the sperm plasma membrane, as well as alters some parameters of intracellular calcium (Ca 2+ i ) dynamics (reported previously by Kurokawa and Fissore (2003)). Herein, we extend these studies to determine if ICSI alters the activity of the Ca 2+ -dependent protein, Ca 2+ /calmodulin-dependent kinase II (CaMKII), which is responsible for the completion of meiosis in vertebrate eggs. After ICSI or in vitro fertilization (IVF), individual mouse eggs were monitored for their relative changes in both Ca 2+ i and CaMKII activity during the first Ca 2+ i rise and a subsequent rise associated with second polar body extrusion. The duration of the first Ca 2+ i rise was greater in ICSI than in IVF, but the amplitude of the rise was transiently higher for IVF than ICSI. However, a similar mean CaMKII activity was observed in both procedures. During polar body extrusion, the amplitude and duration of the Ca 2+ rises were increased by a small amount in ICSI compared with IVF, whereas the CaMKII activities were similar. Thus, compared with IVF, ICSI is not associated with decreased or delayed CaMKII activity in response to these Ca 2+ signals in the mouse. Key words
Loading next page...

Preview Only. This article cannot be rented because we do not currently have permission from the publisher.