Sjöblom P, Lindahl P E
J Exp Zool. 1986 Aug;239(2):255-61. doi: 10.1002/jez.1402390213.
The effects of 17 beta-estradiol (E2) on sperm-egg interactions in the mouse were investigated. It was shown that E2 induces adhesiveness of the sperm head, expressed as sperm-sperm and sperm-egg binding. Since the concentration dependence of this process was similar to that observed for stimulation of in vitro fertilization by E2, it is suggested that induction of adhesiveness or initiation of processes that cause adhesiveness of the sperm head are of biological significance as preparatory steps for fertilization. Finally, the content of E2 in mouse eggs was determined and found to be 0.2 pg/egg, equally distributed between the oocyte together with the zona pellucida and the follicular cells with their associated intercellular matrix. The intra-ovum concentration is estimated as 10(-6) M.
