| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Article |
a Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Massachusetts 01003
b Instituto de Ciencias Biomedicas de Abel Salazar, Universidade Do Porto, Porto, Portugal
Intracellular calcium ([Ca2+]i) rises are a hallmark of mammalian fertilization and are associated with normal activation of embryonic development. Injection of mammalian sperm cytosolic factor (SCF) into oocytes has been shown to trigger [Ca2+]i rises similar to those observed during fertilization, and to initiate normal embryonic development. However, Ca2+ release has also been shown to be associated with cell death, but the mechanisms of the detrimental effects of Ca2+ stimulation on development have not yet been investigated. Thus, studies were undertaken using SCF to test the effects of [Ca2+]i oscillations on oocyte activation in freshly ovulated and aged oocytes. Injections of 1 mg/ml SCF into freshly ovulated mouse metaphase II oocytes, which evoked Ca2+ responses with low frequency and short duration, induced normal activation and cleavage to the two-cell stage. Conversely, injection of 15 mg/ml SCF, which triggered high-frequency and persistent Ca2+ responses, induced abnormal activation that was characterized by abnormal chromatin configurations, inhibition of DNA synthesis, and lack of first mitotic spindle assembly. More importantly, fertilization-like Ca2+ responses induced by injection of 1 mg/ml SCF triggered cell death, rather than activation, in in vitro-aged oocytes. These oocytes exhibited extensive cytoplasmic and DNA fragmentation that was accompanied by activation of protein caspases, all of which are signs of apoptotic cell death. Fewer similarly aged oocytes that were either unstimulated or activated with 7% ethanol underwent fragmentation. Together, these results suggest that [Ca2+]i oscillations are required to activate freshly ovulated oocytes, but if initiated at abnormally high frequency and duration or if induced in aged oocytes, the [Ca2+]i oscillations may trigger premature termination of embryonic development.
1 These experiments were funded in part by a USDA NRI competitive grant (97–2919) to R.A.F and by funds from CSREES Hatch/USDA project #MAS734 to R.A.F.
2 Correspondence. FAX: 413 545 6326; rfissore{at}vasci.umass.edu
This article has been cited by other articles:
|
|
 |
|
  R. Sa, R. Neves, S. Fernandes, C. Alves, F. Carvalho, J. Silva, N. Cremades, I. Malheiro, A. Barros, and M. Sousa Cytological and Expression Studies and Quantitative Analysis of the Temporal and Stage-Specific Effects of Follicle-Stimulating Hormone and Testosterone During Cocultures of the Normal Human Seminiferous Epithelium Biol Reprod, November 1, 2008; 79(5): 962 - 975. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. E. Swain and T. B. Pool ART failure: oocyte contributions to unsuccessful fertilization Hum. Reprod. Update, September 1, 2008; 14(5): 431 - 446. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S.-Y. Yoon and R. A Fissore Release of phospholipase C {zeta}and [Ca2+]i oscillation-inducing activity during mammalian fertilization Reproduction, November 1, 2007; 134(5): 695 - 704. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M.G. Larman, M.G. Katz-Jaffe, C.B. Sheehan, and D.K. Gardner 1,2-propanediol and the type of cryopreservation procedure adversely affect mouse oocyte physiology Hum. Reprod., January 1, 2007; 22(1): 250 - 259. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Whitaker Calcium at Fertilization and in Early Development Physiol Rev, January 1, 2006; 86(1): 25 - 88. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. G Larman, C. B Sheehan, and D. K Gardner Calcium-free vitrification reduces cryoprotectant-induced zona pellucida hardening and increases fertilization rates in mouse oocytes Reproduction, January 1, 2006; 131(1): 53 - 61. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R Tomashov-Matar, D Tchetchik, A Eldar, R Kaplan-Kraicer, Y Oron, and R Shalgi Strontium-induced rat egg activation Reproduction, October 1, 2005; 130(4): 467 - 474. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Ma, D. Zhang, Y. Hou, Y.-H. Li, Q.-Y. Sun, X.-F. Sun, and W.-H. Wang Reduced Expression of MAD2, BCL2, and MAP Kinase Activity in Pig Oocytes after In Vitro Aging Are Associated with Defects in Sister Chromatid Segregation During Meiosis II and Embryo Fragmentation After Activation Biol Reprod, February 1, 2005; 72(2): 373 - 383. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. P. Fleming, W. Y. Kwong, R. Porter, E. Ursell, I. Fesenko, A. Wilkins, D. J. Miller, A. J. Watkins, and J. J. Eckert The Embryo and Its Future Biol Reprod, October 1, 2004; 71(4): 1046 - 1054. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Halet, R. Tunwell, S. J. Parkinson, and J. Carroll Conventional PKCs regulate the temporal pattern of Ca2+ oscillations at fertilization in mouse eggs J. Cell Biol., March 29, 2004; 164(7): 1033 - 1044. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. C. Gordo, M. Kurokawa, H. Wu, and R. A. Fissore Modifications of the Ca2+ release mechanisms of mouse oocytes by fertilization and by sperm factor Mol. Hum. Reprod., July 1, 2002; 8(7): 619 - 629. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. C. Gordo, P. Rodrigues, M. Kurokawa, T. Jellerette, G. E. Exley, C. Warner, and R. Fissore Intracellular Calcium Oscillations Signal Apoptosis Rather than Activation in In Vitro Aged Mouse Eggs Biol Reprod, June 1, 2002; 66(6): 1828 - 1837. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. G. Knott, K. Poothapillai, H. Wu, C. L. He, R. A. Fissore, and J. M. Robl Porcine Sperm Factor Supports Activation and Development of Bovine Nuclear Transfer Embryos Biol Reprod, April 1, 2002; 66(4): 1095 - 1103. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
