title: The ability of whale haploid spermatogenic cells to induce calcium oscillations and its relevance to oocyte activation.
abstract: Interspecies microinsemination assay was applied to examine the ability of minke whale haploid spermatogenic cells to induce Ca2+ oscillations and oocyte activation. Populations of round spermatids (RS), early-stage elongating spermatids (e-ES), late-stage elongating spermatids (1-ES) and testicular spermatozoa (TS) were cryopreserved in the presence of 7.5% glycerol on board ship in the Antarctic Ocean. Repetitive increases of intracellular Ca2+ concentration occurred in 0, 65, 81 and 96% of BDF1 mouse oocytes injected with the postthaw RS, e-ES, 1-ES and TS, respectively. A normal pattern of the Ca2+ oscillations was observed in 26-47% of the responding oocytes. Most oocytes that exhibited Ca2+ oscillations, regardless of the oscillation pattern, resumed meiosis (83-94%). These results indicate that whale spermatogenic cells acquire SOAF activity, which is closely related to their Ca2+ oscillation-inducing ability at the relatively early stage of spermiogenesis.
authors.affiliation: Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano 386-8567, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Amemiya
authors.forename: M
authors.initials: M
authors.lastname: Hirabayashi
authors.forename: H
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Y
authors.initials: Y
authors.lastname: Fukui
authors.forename: S
authors.initials: S
authors.lastname: Hochi
mesh_terms: D000818:Animals; D000864:Antarctic Regions; D020013:Calcium Signaling; D005260:Female; D006238:Haploidy; D008297:Male; D008540:Meiosis; D051379:Mice; D009865:Oocytes / Q000502:physiology*; D020554:Sperm Injections, Intracytoplasmic; D013084:Sperm-Ovum Interactions; D013087:Spermatids / Q000166:cytology / Q000502:physiology*; D013094:Spermatozoa / Q000502:physiology*