This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sun, F. Z. Articles by Moor, R. M. Search for Related Content PubMed PubMed Citation Articles by Sun, F. Z. Articles by Moor, R. M.

Changes in intracellular calcium concentration in bovine oocytes following penetration by spermatozoa

The pattern of changes in intracellular calcium concentration ([Ca²⁺]_i) in bovine oocytes after penetration by spermatozoa was determined. Dynamic video imaging, using Fura-2 as a probe for intracellular free calcium, showed that activation of oocytes by spermatozoa induced multiple transient increases in [Ca²⁺]_i with a spike interval of 24.2 ± 7.3 min, and that the early transient increases were propagated throughout the oocytes in the form of a wave. Calcium transients at fertilization are involved in the induction of cortical granule exocytosis and the resultant block to polyspermy. The hypothesis that the inhibition of Ca²⁺ release from inositol trisphosphate-sensitive stores would inhibit exocytosis and increase polyspermy was tested by injecting oocytes before fertilization with heparin, a potent inhibitor of inositol trisphosphate-activated Ca²⁺ release. There was no significant difference after fertilization in either [Ca²⁺]_i spikes or in polyspermy rates between control and experimental groups injected with low molecular mass heparin up to a final cytoplasmic concentration of 400 µmol l^–1. We conclude that inositol trisphosphate-independent Ca²⁺ stores may be mobilized during the fertilization of bovine oocytes.

This article has been cited by other articles:

				P.T. Goud, A.P. Goud, L. Leybaert, P.V. Oostveldt, K. Mikoshiba, M.P. Diamond, and M. Dhont Inositol 1,4,5-trisphosphate receptor function in human oocytes: calcium responses and oocyte activation-related phenomena induced by photolytic release of InsP3 are blocked by a specific antibody to the type I receptor Mol. Hum. Reprod., October 1, 2002; 8(10): 912 - 918. [Abstract] [Full Text] [PDF]

				K. D. Campbell, W. A. Reed, and K. L. White Ability of Integrins to Mediate Fertilization, Intracellular Calcium Release, and Parthenogenetic Development in Bovine Oocytes Biol Reprod, June 1, 2000; 62(6): 1702 - 1709. [Abstract] [Full Text]

				T. Tang, J. Dong, X. Huang, and F. Sun Ca(2+) oscillations induced by a cytosolic sperm protein factor are mediated by a maternal machinery that functions only once in mammalian eggs Development, January 3, 2000; 127(5): 1141 - 1150. [Abstract] [PDF]

				C Yue, K. White, W. Reed, and T. Bunch The existence of inositol 1,4,5-trisphosphate and ryanodine receptors in mature bovine oocytes Development, January 8, 1995; 121(8): 2645 - 2654. [Abstract] [PDF]