title: [Oocyte maturation and activation in the common frog and the clawed toad under the action of divalent cations].
abstract: Maturation of Rana temporaria and Xenopus laevis oocytes was induced by solutions containing Mn2+ and Co2+ ions. Completion of oocyte maturation was estimated by the following criteria: (1) appearance of the maturation promoting factor (MPF) in the oocyte cytoplasm and (2) oocyte capacity to activation and formation of male pronuclei from the injected sperm nuclei. X. laevis oocytes matured under the effect of Co2+ ions were shown to contain MPF. Oocytes of both species matured under the effect of either ions could not be activated by pricking with a needle and injected sperm nuclei didn't transform into pronuclei. R. temporaria oocytes matured under the effect of ions in late spring, when natural spawning takes place, showed spontaneous activation.
authors.forename: G P
authors.initials: GP
authors.lastname: Nikiforova
authors.forename: M N
authors.initials: MN
authors.lastname: Skoblina
mesh_terms: D000818:Animals; D002413:Cations, Divalent; D002467:Cell Nucleus / Q000502:physiology; D003035:Cobalt / Q000494:pharmacology; D003593:Cytoplasm / Q000187:drug effects; D005260:Female; D008278:Magnesium Sulfate / Q000494:pharmacology; D008297:Male; D016200:Maturation-Promoting Factor / Q000187:drug effects; D009865:Oocytes / Q000187:drug effects* / Q000254:growth & development; D011374:Progesterone / Q000494:pharmacology; D011896:Rana temporaria; D013077:Sperm Head / Q000502:physiology; D013084:Sperm-Ovum Interactions; D014982:Xenopus laevis
chemical_list: D002413:Cations, Divalent; D003035:Cobalt; D011374:Progesterone; D008278:Magnesium Sulfate; D016200:Maturation-Promoting Factor; C018021:cobaltous chloride
vernacular_title: Sozrevanie i aktivatsiia ootsitov travianoĭ i shportsevoĭ liagushki pod deĭstviem dvukhvalentnykh ionov.